I love it as a tool. I love finding new ways to find great poses and re-use them in ways that completely change their source references. That technique mostly grew out of respecting the art of photography and the work put into it, especially if they are from pose books or pose files like you can find on Deviant Art. Also, the great need to not be sued is a big part of that too!
I rarely use a pose directly as I find it, and if I do, I use it very much like a lose breakdown, not exact details of the anatomy or proportions. Photo reference can be a real trap and show through in the art "I traced this" and that is a bad thing for lots of reasons. If you completely shoot your own photos and that is the style you've developed- that's cool, it's all yours and that is a look many people love. But obviously I enjoy more abstract and cartoony vibe, but I know I'm in the minority there.
Anyway, bla bla bla, here is some fun I had with a Gene Kelly photo- that guy knew how to move!