Of course if something is fun for everybody, then you should do it. However, I think you underestimate one big aspect: consistent character roleplay is a big part of the fun in BM.
When I see a character take an action that is contrary to everything they've shown before for obviously OOC consideration, then I'm not having fun, whether this leads to a war or not.
That's kind of my point.
I mean I took actions with my character Brom that specifically screwed him over, because its what his character would do. My actions with Merlin are all in line with someone who is a greedy ambitious arrogant Duke who wants power.