I clip mine, we started the first time they started jumping to roost on the fence... they were about 7 weeks when we clipped them the first time and when we start seeing clipped feathers in the coop we go through and clip again.
My fence is too high for the hens to get out. I have never clipped..
I used to have a hen named fluff who was picked on a little.. The compost was next to the fence and a few times one of the other hens would come over and she'd try to get out fast and accidentally go over the fence.. When we went to get her she would immediately walk over to us as she had been looking for a way back in.
Now, we're on a farm and the fence is seven or so feet tall and the hens can't fly out, so I don't see much need to clip. Fence doesn't have to be that tall at all.