Not sure this question was to me, but I’ll try to answer 
To my understanding yes, this is the way to go if all of your data is on one GPU. And in my opinion it’s simple enough (but it should go into the tutorial).
If you want to use several GPU’s collaboratively, the solution would become more complicated though. I have no idea how that would work. For instance, to the best of my knowledge, you can pass several tensors with a different GPU each. Maybe @ptrblck could give some hints on that?