Joe is Right ... Again
 

The motor rotor inertia is a huge factor in dynamic loading. The factor is for like 3 or 4 to 1 when you run into a wall (or other robot). Picture this: Your 20,000 RPM motor is cruising along and BAM!! all of a sudden it has to go to 0 RPM in no time flat. Severe loading condition. As more of us realize we need more power (ie more motors) we will find various ways to couple the motors and if we are not careful, drive trains will shatter from the collision load and the reason will not be obvious. Normally, when things break one would look at the output, because of the higher loading; but if dynamic collision occurs (we call it E-stop in the industrial robot world) the smaller high speed components may be more prone to failure.

Last year's game gave us a false sense of security when it comes to linking motors together. The TechnoKats did an awesome job last year with their dual motor design, but I believe (and I bet Andy has pondered this very thought) that the dual motor design may fail under collision loads due to the very high motor rotor inertia of the Fisher-Drill motor. Anyway, this is a real concern and should be thought about.

-Paul