GW is great for inducing a state of fat loss, but until i see more research, i feel like it hinders anabolism. it mimics a state of starvation and while it spares glycogen and switches energy usage over to fatty acids, I think it also turns off muscle building genes.
My preference would be to bulk when you bulk and cut when you cut. Eat big, lift heavy, etc, while trying to pack on mass. Then after that cycle, do a cutting cycle where you employ things like GW to help shed the fat.
Also, while it's helpful for cholesterol, triglycerides and insulin resistance, it's not the end of the world to have those values be out of whack for 20 weeks and then spend another 20 weeks getting them back in order.
Feast or Famine. Trying to do both at the same time still seems very counterbalanced IMO. Again though, we will probably never see a lot of research done with these kinds of drugs and how it affects maximum muscle growth. It isn't the purpose of them.