I think it's more common that programmers think they know how to do it right
Sure, but I think you missed my point. I'd rather hire someone who understands the issues and uses best practices than someone that just uses best practices without really knowing why they are "best".
I understand enough to know that I don't understand, which might sound self-detrimental
That sounds both honest and like you have a realistic perspective on what you'd need to learn. Those are two other good qualities that one might look for in an interview.
Regarding how one might fool an interviewer, that's quite true. It depends on the skill of the interviewer as well as his proficiency in the technical material being covered. (Assuming it's a technical interview.)
"My two cents aren't worth a dime.";