Before the update, I used to get one or two chickens stuck in one or two corners of my chicken pens (oak fences). It was not a problem, as you could lead the other chickens over to the stuck ones and they could still breed. Rarely, you'd get a black hole of chickens, with that particular corner absorbing chickens until you had a dozen or so chickens overlapping on that one spot.

Since the 1.1 update, this problem is worse than ever. Now instead of having one or two chickens stuck in certain corners, now I have chickens stuck in every single corner of every single chicken pen. My pens aren't square, but L- or T-shaped, depending on terrain (more visually interesting), so they have as many as 8 corners, and each corner has a chicken stuck in it. Making matters worse, these chickens will not breed, and if left alive too long, they begin to absorb other chickens into that black hole of a corner.

So I kill them, but other chickens just take up those coveted corner spots. Now in order to keep a breeding population, I have to keep an eye on the pens making sure I have more than the corner crouchers, and the free-rangers haven't been absorbed.