Yes they do, sometimes. Wings more often. In a batch of 50 doing 2 at a time in the plucker, I probably had 2 broken or disjointed legs and 3 broken wings. Considering the alternative, I wasn't going to worry about it.
The first time we used one, it was amazing. I researched the process as much as I could and did it by the book. They came out incredibly clean, pin feathers and all. Most of them didn't need any manual feather pulls at all. For the very few that did, it was minimal.
Turkeys are a little different though. We had to work on them a little bit after the plucker.
All in all, I couldn't imagine plucking manually in a production operation. The whole task is miserable enough without something stretching it out as much as plucking would. If you're only doing your own, I wouldn't get anything, or maybe just one of those bench top machines. But for your own plus some sales, the featherman can't be beat.