I've previously used GTG for endurance purposes, to increase my pushup and chin numbers. It worked extremely well!
Now, I remember Pavel mentioning in the "Naked Warrior" that GTG can actually be used for strength. Unfortunately, he does not give guidelines for this when it comes to weights (he only says how to do this with bodyweight exercises).
So has anybody used GTG to get their weight numbers up? If so, does anyone know what kind of loads to use, how frequently, and for how many repetitions?