Some people are simply incapable of accepting that any use of it could ever be bad.
Yes, I don't think any use of it could ever be "bad", but if we replace the word "bad" with "not in-line with table expectations" then the above characterization is inaccurate: there ARE player declarations that are not in line with table expectations, and some of those declarations may be driven by use of OOC knowledge.
BUT I also want to make it 100% clear that the problem is not the OOC knowledge, but rather the potential impact of the action on the game. It's an important distinction, because actions that don't rely on OOC knowledge can have a similar impact. It's the impact that matters, not the thought process that led to the action.
AND we think the solution is not to veto their choice, but to make sure they realize that the adjudicated outcome might not be what they expect.
So metagaming is the not the problem, and banning character thoughts/actions is not the solution.