It's a tough one. I'm struggling with IWANB at the moment, too. I put it down to winter. Can't ride the summer bike as it's too crappy on the roads (and my STIs aren't yet refitted after their trip to Shimano) and I just want to ride something that's quick (forgetting that a new CF bike won't make me any quicker whatsoever).

Keep your bike and get some Ksyriums, man, that's a nice bike and you will have the satisfaction of being immune to IWANB. 'Til the next time anyway.