Mediocrity?

There was a discussion recently about what Mastery is and my thoughts went immediately to doing, whatever you're doing, to the best of your ability. That presented another problem for me: I concentrate on one thing so much that other things slip into mediocrity.

In explanation. My training hasn't gone well because I've been trying to give my shoulder as much rest as possible. It is so nice not being in constant pain anymore! I've been concentrating on doing one thing to the expense of another.

Right now I'm in the midst of my 28 week PDC (Permaculture Design Course), which causes me to focus on watching my video classes for those before I watch the video classes for Kung Fu.

What I'm trying to say is, in order to get everything done, I seem to have to change the target of my focus. I feel like I can only truly focus on one thing at a time. Focus most on one thing for a time because of a deadline or something. Then focus on the next thing for a time because of some other parameter. There seems to be a sort of cyclical target for focusing. I'm pretty sure it's not the best way, it's just what happens, and I don't know another way.