Unit 1, No one to ask

One idea. Authority is a pure function of the certificate set, so every replica computes the same answer in any order with no referee. Yes.

Beats serve it. All eight. Beat 5 introduces the two note kinds; that is vocabulary the idea needs, not a second idea.

Metaphor. The bag carries it and the script stops before saying how the answer is computed. Good.

Assumptions. Nothing beyond the stated audience.

Misconception. Corrected at beats 2 and 4.

Length. 75 seconds is right for this idea. Not padded, not thin. Beat 3's "the document forks" is a small overstatement; the devices diverge on whether to accept Carol's edits. Say that instead.

Unit 2, Authority is a live route

One idea. A delegation carries no proof; the verifier searches the set for a live route. Beats 5 to 7 demonstrate late binding, implicit death and revival as consequences. That is defensible as demonstration, but beat 7 is unit 10's content in miniature. Keep it only if unit 10 is framed as building on it rather than re-introducing it.

Beats serve it. Yes.

Metaphor. The ticket is the planned contrast and is dropped cleanly at beat 3. The card says to state that current flows from the socket outward, and the script never says it. Beat 4 phrases it as "an unbroken chain of strips from you back to the wall", which is the reverse direction the shared visual language warns about.

Assumptions. "Revoked" at beat 6 rests on unit 1 beat 5's one line, which is enough. The field names issuer, audience and subject are never spoken, yet unit 5 beat 5 says "the subject field". Name the subject here at beat 2.

Misconception. Addressed at beats 1, 4 and 9.

Length. Nine beats in 92 seconds is brisk. Beat 5 is the crux and gets three short sentences. Give late binding one more sentence.

Unit 3, Weakest link, best chain

One idea. Minimum along a route, maximum across routes; levels clamp, never reject. Yes.

Beats serve it. Beat 1's second sentence, that relay makes an untrusted server a first-class member of the graph, is an aside about sync, which the series scopes out. Cut it to "relay carries content it cannot read".

Metaphor. The breaker is flagged as a stretch once, as planned. Good.

Assumptions. Beat 1 names Admin as a level with no meaning attached until unit 7. One clause, "admin acts on the wiring itself; unit 7", closes the gap.

Misconception. Addressed at beats 3 and 4.

Length. At 66 seconds it is the shortest unit and it lands. Not padded, not thin.

Unit 4, The socket installs itself

One idea. A subject bootstraps by signing one edge to a root role and destroying its key. The card itself says the unit "also introduces everything is a key". That is a setup fact, not a second idea, but "also" on a card is exactly what the guide forbids. Reword the card.

Beats serve it. Beat 7 carries two things: the creator is not special, and a retained key must be guarded. The second sentence belongs with unit 13 beat 7 and should move there.

Metaphor. The electrician is on the card and never in the script. The script carries the idea without it. Either speak it or drop it from the card.

Assumptions. The viewer is left asking how the creator gets into Owners, since the document key signs only one edge. The answer, that Owners' own fresh key signs the creator in and is then discarded, arrives only in unit 5 beat 2. One clause in beat 3 fixes it.

Misconception. Addressed at beat 7.

Length. 70 seconds is slightly thin. The missing clause above and splitting beat 7 fill it.

Unit 5, Membership is a promise about the future

One idea. The subject field is a scope; a role as subject is membership and carries whatever the role reaches, now and later. Yes.

Beats serve it. Beat 7, "Revoke one membership and they are out of all fifty", is revocation and cascade a unit early. It is a preview, not an explanation, and it is the strongest line in the unit. Keep it, knowing it leans on unit 6.

Metaphor. The card's "a strip with many sockets on it" muddles outlets on the strip with wall sockets the strip is wired into. The script's visual, supplies as cords from sockets into the strip, is right. Fix the card wording.

Assumptions. Covered.

Misconception. Addressed at beat 2.

Length. 87 seconds works.

Unit 6, Revocation unplugs a cord, not a person

One idea. A revocation names one delegation by hash, deletes nothing, and cascade is implicit. Yes.

Beats serve it. All eight.

Metaphor. Holds throughout.

Assumptions. Beat 3 assumes Dan may revoke, which unit 7 explains. Dan issued the certificate, so it is fine.

Misconception. Addressed at beats 1, 2 and 5.

Length. 74 seconds is right.

Unit 7, Who may pull a plug

One idea. Validity is unconditional; effect is scoped to the signer's standing in three tiers. Yes, though it is the widest single idea in the series.

Beats serve it. All eight. Beat 3's key-leak rationale is the right one sentence of motivation.

Metaphor. Beat 3's visual, "either hand can tear it", breaks the shared rule that revocation is unplugging, never an eraser. Make it an unplug.

Assumptions. Covered.

Misconception. The stated misconception, "a higher admin can revoke anything below them in some hierarchy", is nearly true in Keyline: an admin can cut anything routing through their rooms, however deep. What the script actually corrects is "admin is a rank" at beat 8 and "an admin can cut the supply feeding their own room" at beat 6. Restate the misconception as one of those.

Length. 97 seconds for three tiers, composition, seniority and inertness is dense. Beats 2 and 4 each deserve one more sentence. This unit should use its full target.

Unit 8, Reach is forever

One idea. Reach is computed as if no revocation existed, so it only grows, which is what makes concurrent revocations land identically. Yes.

Beats serve it. All eight. Beat 8 is a clean handoff to unit 11.

Metaphor. The two-layer map holds.

Assumptions. Covered.

Misconception. Addressed at beats 3 and 6.

Length. 87 seconds and the crux at beat 3 has room. Good.

Unit 9, You cannot un-revoke, you grant again

One idea. Borderline. Beats 1 to 3 say revocations are permanent, which unit 8 beat 5 already established. Beats 4 to 7 are a distinct mechanism: identical bytes collide with the revoked twin, so a heal needs a citation. The check question tests only the second. Either frame the idea as "a heal must be a fresh hash" and shrink beats 1 to 3 to one recap beat, or accept that the citation is the real unit.

Beats serve it. Beat 1's title card restates unit 8.

Metaphor. The cut cord plus tag holds.

Assumptions. Covered.

Misconception. Both halves addressed, at beats 2 and 4.

Length. 86 seconds. Beat 7 is compressed and, per the accuracy pass, wrong.

Unit 10, Dead is not revoked

One idea. Re-adding a key revives everything it issued, which is a repair and a hazard. Yes.

Beats serve it. All eight. Beat 3's sentence "Everyone comes back except Eve is one re-add and one revocation" does not read aloud; it needs a signal such as "the rule 'everyone except Eve' costs one re-add and one revocation".

Metaphor. Holds.

Assumptions. "Cited grant" at beat 2 relies on unit 9. Covered.

Misconception. Addressed at beats 2 and 4.

Length. 81 seconds works.

Unit 11, The ex-admin's keys

One idea. A removed admin keeps frozen reach, so durable removal needs rotation. Yes.

Beats serve it. Beat 7, the BeeKEM comparison, imports "the encryption layer" and "key rotation", which the audience has not been given and the parking list parks. It is a second analogy. Cut it.

Metaphor. The card's "you cannot change those locks" is never spoken; beat 1's "keyrings never shrink" does the job. Fine.

Assumptions. Covered. Beat 5's "late binding again" leans on unit 2.

Misconception. Addressed at beats 1 and 2.

Length. 84 seconds against the series' longest target. Beat 4 compresses the whole rotation recipe into four sentences and beat 6 carries three separate facts. Expand both. This is the headline sharp edge.

Unit 12, Admin over a document is only the power to destroy it

One idea. Two. Beats 1 to 5 are "Admin over an unrotatable subject puts it in reach forever, so supply at Edit". Beat 6 is constitutional flatness, a distinct design rule about roles that the source gives its own section, in four spoken sentences. Either make it a unit or park it.

Beats serve it. Beat 6, as above.

Metaphor. The fixed socket holds.

Assumptions. Beat 3's premise, "If Members held admin over the doc", is only possible in an Admin-rooted document, because the supply's level is capped by the root edge. The rooting level is not introduced until unit 13 beat 3. The check question is unanswerable as asked.

Misconception. Addressed at beat 4.

Length. 73 seconds. Beat 6 is too compressed; beats 3 and 5 need the rooting-level clause.

Unit 13, The root cannot rotate

One idea. More than one. Beats 1, 2, 5 and 6 are "the root role is append-only, so keep it tiny". Beats 3, 4 and 7 are "rooting level and the retained key", which is the design choice unit 12 needs. Split.

Beats serve it. Beats 3 and 4 fight each other as written: beat 3 says "Root at edit", beat 4 says even at edit an ex-owner can brick the document, and the payoff that makes Edit worth it, clean re-rooting with a retained key, arrives at beat 7 without saying it depends on Edit rooting. The viewer leaves not knowing why Edit was recommended.

Metaphor. Electrician on the card, never spoken. Fine.

Assumptions. Covered.

Misconception. Addressed at beats 1, 2 and 5.

Length. 96 seconds for seven distinct facts. Dense. Splitting fixes it.

Unit 14, Who can cut you off has an exact answer

One idea. X can deny Y iff every live route to Y transits X's reach, so availability is a min-cut. Yes.

Beats serve it. All seven. Beat 6's pyramid is a new shape not on the card.

Metaphor. "Two cords through the same room are one cord" is the strongest line in the back half. Holds.

Assumptions. Beat 4's "only admins" depends on the memberships-only shape from the patterns doc, which no unit introduces.

Misconception. Addressed at beats 3 and 4.

Length. 78 seconds works; beat 2 could slow down for a worked floor plan.

Unit 15, One honest peer

One idea. Two. Beats 1 to 4 and 7 are "a withheld revocation can only be delayed; one honest peer repairs it". Beat 6 is the closure, a named concept with its own visual, five sentences, and no mention in the idea sentence. Beat 5, missing delegations fail open, is borderline but supports the window discussion.

Beats serve it. Beat 6, as above.

Metaphor. The recall notice is on the card and never spoken. The script uses the red note and the bag. Either speak it or drop it.

Assumptions. Covered.

Misconception. Addressed at beats 3 and 4.

Length. 89 seconds. Beat 6 is compressed; cutting it or giving it a unit fixes both problems.

Thirteen findings. The first ten change what the viewer will believe; the last three are precision or scope.

U2 beat 2. "Four fields... That is all." README, Delegations table, lists five: issuer, audience, subject, power and the optional citation. Unit 9 beat 5 then adds a field the viewer was told does not exist.

U5 card, why it matters. "fifty certificates instead of five hundred". Ten memberships plus fifty supplies is sixty.

U5 beat 8. "If Members is later given admin over something, every member gets it." Levels clamp. An Edit member gets Edit. README, Attenuation; patterns, Roles: "Members at Edit or Read merely transit."

U9 beat 7. The nonce argument is inverted. Script: "A nonce fails open: forget it and the heal silently matches the revoked twin." Alternatives, "A random nonce instead of citation": a nonce makes two accidental issuances two independently live certificates, revoking one leaves the other, and that is the fail-open. The silent collision with the revoked twin is the citation's fail-closed behaviour, not the nonce's failure. The beat's second half, that a citation can only be written by someone who has seen the revocation, is correct.

U12 beat 3. "If Members held admin over the doc" is only possible in an Admin-rooted document. Patterns, Rotating a Role: "The role's level is capped by its supply and by everything above it, so supplying below Admin, or rooting the document below Admin, keeps the subject out of reach." The script states neither condition, and the check question, "Members is supplied at Admin over the document", has answer no in an Edit-rooted document and yes in an Admin-rooted one.

U12 beat 5. "The document stays off everyone's keyring." False for an Admin-rooted document, where every Owners admin ever has Doc in reach regardless of supply level. Patterns, Rooting Level table.

U13 beat 3. "Rooted at edit, nobody can revoke the root edge at all." README, Who Can Revoke the Root Edge: revocable by nobody "provided the root role's key was discarded after creation", and a retained subject key always can. The proviso is missing.

U13 beat 7. "A retained document key in cold storage is the one escape hatch: it can re-root." Only for an Edit-rooted document. README, The Root Role is Append-Only: "For an Admin-rooted document the retained key buys nothing durable."

U14 beat 4. "The griefer set is the people who ever held admin on your routes, and nobody else." Overstated. Admin reach includes the signer's own node, so anyone whose own hop lies on all of your routes can cut you, admin or not. Patterns, Memberships as the Only Shape: "An invitation rides its inviter... removing Carol removes Eve." README, Griefing conditions "only admins are in the set" on that convention, and even then an inviter's own hop is a cut. Add "unless your only route runs through their own strip".

U15 beat 5. "Fuller sync only ever tightens." Coverage only expands, but access can widen too as delegations arrive. README, Partial Visibility: "A missing delegation usually costs access, but it can also grant it." Say coverage tightens, not sync.

U1 beat 3. "the document forks." Overstated; the replicas disagree about whether to accept an edit. Minor.

U7 beat 4. "The set of rooms on your keyring is your admin reach." README glossary adds "plus its own node". The script handles the own node as tier 1 separately, so this is consistent, but the sentence as spoken is incomplete.

U11 beat 4 and beat 7. Beat 4's rotation recipe omits that Members prime's own key signs the surviving admins' creation edges before being discarded (patterns, Rotating a Role, step 1). Not wrong, but the viewer who learned the move in unit 5 beat 2 will ask who signs the first roster. Beat 7's BeeKEM table is accurate to README, The Ex-Admin Sharp Edge, but out of the series' scope.

Checked and holding against the source: unit 7's three tiers and seniority by geometry; unit 8's two passes and three protections; unit 9's "revoke cannot name a revocation" and the zero-semantics citation; unit 10's three removal tiers; unit 11's survivors' reach growing and the ex-admin's revocations lapsing; unit 13's duels and keep-it-tiny; unit 14's theorem, min-cut, deny-only, attributable and the inverse relation; unit 15's closure definition and the one-honest-peer argument.

Order. Right except at 12 and 13. Unit 12 needs the rooting level, which sits in unit 13 beat 3. Move rooting level into unit 12, where it belongs with "supply at Edit"; unit 13 is then purely "the root role is append-only". Unit 5 beat 7 leans on unit 6 as a preview, which is acceptable. Unit 14 leans on an unintroduced convention, below.

Required material the series lacks.

Constitutional flatness is squeezed into unit 12 beat 6 and the memberships-only shape is absent, yet unit 14 beat 4's headline claim depends on both. Either give flatness and memberships-only one unit between 12 and 14, or soften unit 14 beat 4.

The dormant node. Unit 11 beat 6 says Bob's keys "open rooms that route nothing", which plants exactly the intuition README corrects under The Ex-Admin Sharp Edge: the old role is dormant, not dead, and anyone who re-supplies it revives every former admin. The parking list parks sealing, but the hazard itself needs one sentence in unit 11, the way unit 10 pairs repair with hazard.

Nothing else in the parking list is required. Pinning, caretakers, retain, evaluation cost and the AND/OR formalism can stay parked. Unit 14's "two cords through the same room are one cord" carries the tree-not-path intuition well enough.

Count. Fifteen is close. The guide's named failure mode, three ideas in a unit, recurs in units 12, 13 and 15. The fix: unit 12 absorbs rooting level and loses flatness; flatness and memberships-only become one unit; unit 13 keeps root-cannot-rotate, duels, keep-tiny and the retained key with the Edit proviso; unit 15 drops closure or gives it a unit. That is sixteen or seventeen units. Unit 9 can shrink its permanence recap to one beat without loss.

Visual language. Holds across units 2 to 14. Three breaks: unit 7 beat 3's torn note violates "never an eraser"; unit 15's dashed closure boundary collides with dashed rooms meaning admin reach; unit 14's pyramid is unplanned. Four cards name a metaphor the script never speaks: the electrician in units 4 and 13, the locks in unit 11, the recall notice in unit 15. The scripts work without them, so the cards should match the scripts rather than the other way round.

Lengths. Nothing is padded. Compressed: unit 7, unit 11, unit 12 beat 6, unit 13, unit 15 beat 6. All of these are the units carrying extra ideas or the series' sharpest claims, which is the usual sign.