docs: R5's debt was over-reported, because the measurement counted a proxy

The record said four chapters offer several spellings at equal weight, on the
evidence that they carry many code blocks and no <details>. That counted a proxy
instead of the property. A section with five code blocks is usually five
features documented in sequence -- chapter 20's are glob exclusion, per-glob
flags and generated files -- or one continuous session, which is what chapter
00's six blocks are. Folding any of those away would break what they belong to.

Measured on the property -- a section that offers ALTERNATIVES at equal weight,
found by the markers that introduce one -- the whole tree returns three hits,
and none is a choice presented to a reader: two are prose about what is
accepted, one is a comment in a command line. R5's real debt after 05 and 01 is
close to zero, and what remains is to apply the rule as new alternatives appear.

This is the third criterion in this batch that counted something adjacent to the
property: headings containing "test" for chapters that explain testing,
substring spellings for the lookup index, code blocks for offered alternatives.
The skill says a criterion must not be a substring search; the variant now named
beside it is COUNTING A PROXY, which survives review precisely because the
number is real.

Author: speak-agent

.agents/docs/2026-09-08-the-documentation-as-a-book.md

@@ -379,15 +379,36 @@ reader can reproduce.
 reproduced on the current release, and each of which a reader could otherwise
 only discover by hitting it.
 
-### 11.2 Four chapters present several spellings as equals
-
-`04` (50 code blocks), `20` (35), `30` (37) and `40` (33) carry no `<details>`,
-which means every spelling in them is offered to the reader at the same weight.
-R5 says one recommended path in the body and the rest folded away. `05` is the
-one section converted so far, and it is the shape the other four follow.
-
-*Criterion:* a reader who reads only the body and opens nothing can do the thing
-correctly without choosing.
+### 11.2 R5's debt was over-reported, and the measurement is why
+
+The first reading said four chapters present several spellings as equals, on the
+evidence that `04`, `20`, `30` and `40` carry many code blocks and no
+`<details>`. **That counted a proxy instead of the property.** A section with
+five code blocks is usually five features documented in sequence — `20`'s are
+glob exclusion, per-glob flags and generated files — or one continuous session,
+which is what chapter `00`'s six blocks are. Folding any of those away would
+break the thing they belong to.
+
+Measured on the property instead — a section that *offers alternatives at equal
+weight*, marked by "alternatively", "either form", "也可以", "等价写法" — the
+whole tree returns **three** hits, and none of the three is a choice presented
+to a reader: two are prose about what is accepted, one is a comment in a command
+line.
+
+So R5's real debt after `05` (the dependency spellings) and `01` (the two
+installs) is close to zero. What remains is to apply the rule as new
+alternatives appear, not to convert a backlog.
+
+*Criterion, restated so it is not measured by proxy again:* a reader who reads
+only the body and opens nothing can do the thing correctly **without choosing
+between two ways of doing it**.
+
+> Third time in this batch that a criterion counted something adjacent to the
+> property: headings containing "test" for chapters that explain testing,
+> substring spellings for a lookup index, code blocks for offered alternatives.
+> The skill already says a criterion must not be a substring search; the variant
+> worth naming is **counting a proxy**, which passes review because the number
+> is real.
 
 ### 11.3 The manifest reference still holds worked examples and an appendix