Well, if you'd quoted the other part of what I said in that paragraph, it wouldn't have come across as putting words in your mouth. My real question was in the part you didn't quote:fusangite said:People keep putting these words in my mouth. If you cannot offer a credible justification for your character doing something, they shouldn't do it. So no -- I don't think people's characters should make decisions that are "completely irrational from their characters' point of view."
Although granted, you did make the caveat that in-game justification is a requirement. Of course, if you do that, I don't see what the big deal is. You can never completely excise metagame considerations from play, so it seems to be an implicit assumption of anyone who wants to minimize it that you don't really have a problem with it per se as long as your decisions are justified in game. Maybe some people want to push even beyond that where possible, but I don't really see how that could be done anyway.