I don't use anatomy reference as much as I used to, but sometimes I still do, especially for complicated poses, expressions, or hand positions. I actually looked up several references for expressions today for the page I'm working on, and ended up taking a photo of my own fist for a reference at the angle I wanted. It helps.
I also use reference a lot for environments, objects, and animals, and I use it A LOT to get the color/lighting effects right. Because I use markers, and I get ONE SHOT at getting my colors down correctly. So I do a lot of research and a lot of practice.
Btw, if anyone wants the fist pic for reference, here you go: