I read an MBTI description that said don't hook up with INTPs because they act like a J and slowly as you get to know them they return to their P and became lazy and messy.
Well of course it's true that people act a certain way until they are comfortable around other people, but is that 'certain way' a projection of the Id? I think it would sort of be like "Haha you think this is how I really am, but it's not, while I fool you into letting your guard down". Maybe in an attempt to protect the PoLR?
On one occasion I've noticed a distinct difference in behavior. An ESTP, new to the group, became an exact lookalike of an ESTJ,. She was all gung ho about work and everything and was really straight to the point. Once, integrated however, the
began to show.