Oh? First I've heard of that, and I do not see it mentioned on the PGLister_Announce wiki page. It definitely should be.
Yeah, that's clearly an oversight on the wiki page.
We also try to trap the word unsubscribe in the beginning of the body to moderate those. But that one misses a lot of combinations, because we don't want to get stuck in the same situation as the old mj2 which captured way too much.
