It's not a truce, it's just the herding behavior. You can get very few people on any side to defend against a mob, or attack a new front. Either no one defends that front, or everyone does, leaving some other area vacant, and the cycle starts anew.
With all due respect anton, you do exactly the same thing. Many of us are guilty of it. I don't play for hours, and don't give a nut lik about the war- I just head where there's some action most nights. That normally means finding a fight in progress, without regard for the overall distribution of fights between countries.