Carl, I have a lot of cutoffs from cedar siding so birdhouses are on my to-do for this winter and I hope you're right.
I've pretty much determined that the center spot focus, at least with 300 X2 is at least double the little square in the viewfinder. That leads to issues when there is a close object and my bird is just to the side of it, etc. From what I've read a camera like the 1Dx is much better at locking focus and holding onto moving objects. I was using a tripod and gimbal so the problem was not me shaking like a leaf.
At any rate I'm happy to be using the 6D based on IQ, even if I lose some shots.
Other than waxwing shots I don't have much to post right now
So, another dragon with 6D 300 X2.