Originally Posted by DannyZRC
spool, nothing so complicated necessary as talking about zero traction (ice, btw, is about as zero as those rollers).
they turn the TCS/ESP off on the cars they want to look bad, and leave it on for the car they are promoting.
all modern cars have systems that will brake spinning wheels, the only real differentiator in AWD systems is how elegantly the braking is accomplished, and how much torque capacity there is in the secondary drive system for cars without center diffs.
the main difference between rollers and ice is that if you both any of those vehicles in this test with all four wheels on ice, they will get themselves moving. If you put all four wheels on those rollers, all of the vehicles would get stuck and would require intervention.
The only time you'll have zero traction in "real" world driving is if one or more wheels are off the ground, which will rarely happy unless you're off-roading (in which case you'll want a true 4WD system with locking center, front, and rear differentials anyways), in the ditch, or rolled over up-side-down because of an accident.