I'd love to see the advocates of alpha rolls try to alpha roll a wolf.
I don't think you need to slam a dog on its back to earn respect. In fact by showing that kind of instability you'll probably lose it. I am alpha because I control my dog's food, I control the affection/petting/belly rubs, I control when he goes out, I control the toys, I can even control where and when he sleeps if I want to. Being in control of thos important things lets my dog know that I am, in fact, the boss.
Now, if he was free fed, had a doggie door, had toys all over, was allowed to sleep anywhere he wanted, and fawned over constantly for no good reason... then of course I'd have "dominance" issues! You'd have to have a really, really laid-back dog for them not to take advantage of that.
Things like NILIF are just good common sense, but I love them because they make people aware of the fact that they don't have to be scaring their dog into submission in order to gain their respect and obedience.
That being said, I could tackle my dog right now and hold him on his back and he wouldn't care at all. Why? Because he's not a wolf. He doesn't view my rolling him over as a threat, he views it as a gesture of affection. I have rolled him on his back since the day I got him, he's used to it and thinks nothing of it.
I agree with Gempress about holding puppies on their backs. It -is- a very submissive position and I think it's a good thing to get them used to being handled in every way possible. (Which is what I really love about Dakota, I can do literally anything to that dog and he will stand for it.)