With cars and motorcycles, the performance is oftentimes limited by traction, so having extra wheels improves the traction and off-road performance.
With bicycles, you very seldom are limited by traction, and usually be lack of power, so adding the 2-WD increases weight and complexity, but doesn't necessarily help performance that much. If you got in just the right circumstances, it'd be great.
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"be careful this rando stuff is addictive and dan's the 'pusher'."