diff --git a/admin_ui_cleanup.md b/admin_ui_cleanup.md
index 33b040e..443ae64 100644
--- a/admin_ui_cleanup.md
+++ b/admin_ui_cleanup.md
@@ -447,6 +447,23 @@ A proof about the container is not a proof about the member, and that substituti
 because the evidence is real and the reasoning feels airtight. Ask explicitly: *does my evidence
 range over exactly the thing I am ruling out, or over something that contains it?*
 
+**Re-read the comments inside your own diff — a change that invalidates prose usually ships the
+prose.** A commit that removed a modal's self-closing behaviour left two comments in the same file,
+in the same commit, still describing the modal as self-closing. The code and its explanation
+contradicted each other inside one change, and the diff read as coherent because a reviewer checks
+whether the *code* is right, not whether the surrounding sentences survived it. Grep your own diff
+for comments in the touched regions and ask what each one asserts. This is the most common way a
+correct fix ships a false claim, and it is invisible afterwards: the next reader trusts the comment.
+
+**When a modal misbehaves on refresh, the property to check is whether it holds any state of its
+own.** A modal that is a *pure projection of a list* cannot distinguish "paged out of view" from
+"deleted", so any list change is indistinguishable from the record vanishing. That — not the presence
+of a particular field — is the test. In one sweep, four detail surfaces split exactly on it: the two
+that fetch detail by id survive a page change with usable content, the two that project from the list
+are page-scoped whether or not anyone intended them to be, and only the latter two need their held id
+cleared on paging. Checking for the *field* would have found the same two here by luck; checking for
+*state of its own* is what generalises.
+
 **A "what I could not establish" section confers unearned credibility on everything above it.**
 Listing your limitations is good practice and this playbook demands it — but be aware of what it does
 to a reader: the presence of a limitations section is taken as evidence that the rest was held to