And popa’s the biggest, because he neglected to point out that the Shach says it’s okay if it wasn’t washed thoroughly, mashma that if it wasn’t washed at all, it’s a problem.
I disagree. I did in fact look it up before I posted to get the citation, and noticed that, and thought of that diyuk, but do not think it is correct. I think the shach is just talking about a normal case where this would happen, since people don’t usually cook in filthy pots.
Haga atzmecha–do you think the shach would bury that halacha in a diyuk like that? If he wanted to distinguish, he would say that.