To think, or not to think?

Too much thinking about your playing can be just as bad as too little. Both can end poorly. A performance can be crippled by over-thinking as well as by recklessness. Somewhere there is a safe middle ground between brains and no brains, between too much caution and none at all.

Think about this: The question is not about thinking but about sounding. A total focus on the beauty of the product will eliminate thousands of useless notes and extraneous noodling that nobody wants to hear.  

A great performance is about great music-making. That priority should drive every practice session.  Think not about how you are feeling, but what the audience will want to hear.