In a leap of education, last night I read quite a few different articles about ESC timing and motor sizing. I couldn’t have been more wrong about my initial thoughts of what that parameter actually did!  

I was thinking that the timing setting was related to PPM, but its not, it has absolutely nothing to do with the RC side of the ESC. It actually has to do with the motor side of the ESC (which makes waaayyy more sense, DUURR).

Basically (as i now understand it), ESC timing gives the ESC some basic knowledge about how to better handle driving the brushless motor.  In short, Medium timing is always recommended. If its a high RPM high pole-count motor, you can use High timing to get more performance out of the motor.  If you want to conserve battery, and keep the motor cooler, Low timing is recommended.  There is a great formula available to determine which is best for your voltage/kv combination (Kv x volts x pole count / 20) pulled from the blog post here http://www.helifreak.com/showthread.php?t=249106