Well, some recent hindsight analysis (during the eridu radical-feminist debacle) allowed me to notice that it seems highly likely that nearly all female feminists I've encountered in person with common knowledge of such were mostly of the kind that had one or few strong very bad near-type personal experiences with men, or many small but memorable such near-type experiences. The kinds you'd probably expect from a stereotypical scenario of "The Father is Master and Law of the House" or a poor waitress working late shifts at a café on the same street corner as a strip club.

So in my case I probably wasn't dealing only with "feminists", but at the same time with individuals taken with a widespread personal fear or anger towards men, in nearly all the cases that produced these kinds of strong reactions. This might be due to statistical coincidence (not that particularly unlikely) or to some behavior that causes other types of feminists to not identify themselves as such when dealing with me, or to some other cause.

It may very well be that the A scenario you describe actually does happen to me sometimes, but with the other participant(s) simply not identifying themselves as feminists at all. If so, I either never ran them through my mental model of feminists for a pattern-matching, reverse-ideological-turing-test thinghy, or my model is sufficiently incorrect/imprecise that they actually failed said test.

In my personal (social) experiences, feminists overall are not as vicious most of the time =)

I kind of suspected this to be the case, because if the contrary were true, the feminist movement as a whole would be spectacularly self-hindering and shooting itself in the foot constantly, since such behavior as I've observed would basically cause very destructive conflict and wouldn't actually help further their goals.