No, with AMG it isn't variations of the same sample. It is different samples altogether. If you put in a row of 127's, you'll still get variation, because it brings up some of the lower layers to the same volume. Here you go, an example:
https://dl.dropboxusercontent.com/u/630473/AMG.mp3
Just a rough example. Remember, you can dial in the most appropriate amount of randomization on a global level, and also on a kitpiece level. So if you like the way it affects your kick and snare, but not your ride... you can fix the ride without screwing up your kick and snare.
Classic round robin is a cyclical pattern. So if you send in a series of 127's... you get layer 1, 2, 3, 4, 5, 6, 7, 8, 1, 2, 3, 4, 5, 6, 7, 8, 1, 2, 3, 4, 5, 6, 7, 8, etc.... This results in patterns of sound that are a dead give away for machine-gunning. Sometimes they change it slightly so that the direction is 'random' instead of 'forward' or 'backwards' or whatever... this is basically no different from our AMG methodology, except our method allows for potentially a wider range of samples to be addressed. We're not limiting you to just 4 or 5 variations, or however many competing products have.
There aren't any phasing issues and realistically, when do you ever *actually* send in a whole series of just one velocity layer?? I'd suggest whatever program you use, if you're doing that, it's bad programming - imho.