the main problem with buying pups from an "un-handle-able" mom is that you don't know if the reason she can't be handled is a training issue (did they raise her to be super intolerant of humans?) or does she have temperament problems that could be genetic?
Nature or nurture, pups learn a lot of their behavior towards humans from the dam before leaving the litter. If mom was so unmanageable, how were the pups handled for health checks after birth? Did they just get left with Mom and hope that none of them died or failed to thrive?
No, I don't own LGD breeds. I DO own other powerful breeds, plus the "alpha roll" theory being bad is pure common sense.
I will say that, yes, I alpha rolled a dog once. And yes I knew when I did it that there was a chance that I could get hurt (actually I realized that AFTER I did it) but it was an emergency situation. We had a lab that had disappeared for over a month. We found that someone had a lab that looked just like him chained in their yard. We stopped to ask about it and they denied it being our dog. I said "oh ok. Because my dog is microchipped so it would be obvious if he was mine" and drove home. The next morning, my dog was outside waiting on the porch and the next time I drove by their place they had no dog, but that's a little off-topic. When he came back, he was over-weight and always ate like he was starving. He was super-excited to be back on his raw diet, but had developed some food aggression. I had been working with him on that and he was in the yard chewing on a bone while I worked in the garden. My DD, 3 yrs old, came running out of the house and he jumped up growling and started towards her. I basically tackled him and yes I was right in his face. I didn't bark like an idiot, I said "what the *^^* do you think you are doing??" He didn't struggle much, probably because he had never really been anything other than a submissive dog. Later I realized that I would have been toast if he decided to put up a fight, but Mama Bear instinct had kicked in and I think that attitude is what put him into submission, not the fact that he thought "oh she knows how to alpha roll, she must be head dog"
Being "dominant" isn't a matter of doing alpha rolls and standing over the dog and making them submissive. It's just THERE, for lack of a better word. I don't like all of Milan's techniques but I can't deny that he does have a presence with dogs when he walks into a room. We all know people like that; it's like an aura around them. They come into a room and everyone takes notice. You don't need an innate power, just confidence . 99% of dogs aren't little Hitlers with plans to take over the world; they would much prefer that someone else be in charge. So simply laying down some rules for behavior, following through with them, providing food and water, and BAM your dog thinks that you are the king of the world.
If you want to compare dogs to wolves, look at how the "alpha roll" works in the pack. The leader sees someone getting out of line (perhaps a young male that is trying to push up to the table too early). If he is just hungry and doesn't want to wait his turn, then the younger animal will back down and roll HIMSELF over to show "hey, I know you're the boss. Please don't hurt me." If it's just another step in a pattern of a young wolf preparing to challenge the leader, a real fight may or may not break out at the moment, but you know that one is coming soon. There will be a lot more posturing and the younger animal will reluctantly back down. But, it's pretty obvious that one time soon that isn't going to happen and there will be a fight.
Shoot, in the cat world, a lower ranking cat will "roll over" to appease a more dominant cat. I don't see anyone going around saying "alpha roll your cat!!" That would be great to see though and if anyone tries it, please post video when you get back from the ER