Am I practicing wrong or right?

[ZombieChinchilla]

Personally, I think the key to combining studies and illustrations is to pick an illustration with some kind of aspect that you're not familiar with, say horses. You've never drawn them, so in order to make your illustration better you need to study them, practicing their anatomy and construction and so on. You crank out fifty horses, and then when you go back to your illustration, it looks much better than when you had never drawn one.

This method works really well for me, and I think Forrestimel's SB shows it working really well, especially with his last couple pages. You see him doing specific studies and then applying them to finished portfolio pieces.