Dear Ed Miller,
I agree with you, the physical preparation in Disc golf should be determined by the aim to improve the motor control capacity.
This is the “motor learning” factor, not limited by maximal strength or other physical condition capacity (oxidative capacity, lactic acid buffering).
The necessary precondition is to have a good general physical condition (preparedness) that allow you to get a good control of competition motor action (like in golf), this general physical preparation is different from that used for Olympic sport disciplines finalized to increase the power output.
It’s difficult for me to suggest how should be organised this physical preparation, because I am not familiar with the optimal training for an elite golfer.
Nevertheless I hope this generic suggestions can be useful for you.
Yuri Verkhoshansky