Just bustin' your chops. Looked like a good/hard ride.

I agree with your 'towards the front is easier' idea for a couple reasons. The first is that you reduce the accelerations when you're near the front. For me, that's harder than the (sometimes) marginally more wind you end up taking. The other thing is that when you're riding at the front, it is often those days when you're feeling better physically. It makes it seem easier even if the powermeter says otherwise.