I've noticed that, when talking with others more introverted than myself (or at least behaving like it), I tend to adopt a more ENFP role, especially if the other person appears to be distraught. I've often wondered if I do this because it feels like it's what's expected of me (ie. the caring friend) or if I'm just more 'F' than I realize. It may also be that I'm just so used to my Ti being 'abnormal' that I tend to hide it in some unconscious effort to appear 'normal'.
Anyway, I've noticed that when I'm stuck in a situation where I'm more-or-less required to be sociable, I tend to be overly outgoing and goofy, kind of an over-the-top chameleon reaction. However, if I'm in a leadership role and things need to get done, I become more of the strong, silent commander type.
When I'm interacting 1-on-1 with close friends, I return to a much more INTP state.
I guess I mean to say that I'm not sure any behavior is truly abnormal for an INTP, perhaps because INTP doesn't have a specific role of its own in many social settings.