Never heard anything like that before. What a load of rubbish. That would mean that the tail should go up on every hen and down on every cock. And who in their right mind would pull a pigeons beak like that!!!
Back just enjoying club racing for the time being.
I can't say that I've ever heard that one before either !!!
I have however heard other fanciers that will also out birds who's tails go up like that, again personally it's not something I've ever really played much attention too.