I believe what they are talking about is the diff is unloading, basically when one wheel lifts off the ground that tire spins feely, and the diff "unloads" all of it' power to that wheel. For that moment the wheel that is still in contact with the surface has no drive at all.
To cure this you would want to add more droop to that end of the car, softer shock oil, heavier springs.... all depending on the handling problem that is causing the result.
G's RC Raceway- Best off-road track on the east coast...period!!!
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