Yes I've seen dogs do it by both force & by just using their place in the pack to assert a alpha roll.
I think wolves & domestic dogs are a little different so the wolve stuff is a little irrelevent to me.
As for someone saying they are not into crulety & thats what a roll over is, wow..........
I think you have to understand anything you do whilst a dog is in flight or fight responce isn't doing any good as dog has stopped learning so my biggest advice is to not put your dog into a situation that they could respond with that responce.
If the alpha roll was cruel it would be pointless.
I would not use it on just any dog either but their are some that it has made huge changes in.