Hmmmmm, rational as in not colored by introverted feeling? In strict Jungian terms: not colored by our rational function (see what I did there? woot!).
...but that's not what makes ENFPs (ok, just me) withdraw. Or at least, it's not the primary reason. Bad people are a pain in the ass, and probably piss us off more than most, but it's not like I have to hide in my igloo to escape the evil in the world...
nevertheless, my intuition sees a grain of truth in that. Maybe I'll reflect on it as well...
EDIT: I'm totally being off topic as well...
So, to bring it back (loosely), why the hell would Se be more resiliant against Fi's intrusions? Is Se-fueled Fi a different brand altogether? Does the content that it processes affect the process itself? What is the meaning of life? ...K, I'm done.