just my opinion but I think weapons focus + the other requirements are enough to qualify for warchanter status. having to take power attack becomes a significant sacrifice for dual wielding/ dex based combat bards.
It seems clear that the warchanter enhancement is really for MC'd bards to be able to keep pace with song bonuses but I think its shafty for the fightin' type dex bards w/o extra feats to toss away from taking lvls in fighter w/e. Never really considered MC'n my bard till now and still dont want to but it might be worth it even if i take a feat that never gets activated lol
mostly just venting but also interested to hear othe bards opinions on this. Thanks