I agree entirely with that, but from my experience the length of an impact is a lot shorter than that, perhaps a 10th of a second at most. Of course I appreciate there are situations where, say, a large tooth spinning disc burries itself satisfyingly into a sheet of poly, and so will have a longer deceleration, but in most cases impacts last a very very short time- sufficient that the amount of energy produced by the motor that is directly transfered into the opponent is negligable in comparison to the energy the flywheel is transferring. It would be interesting to get a figure on what most people would regard as a typical impact time, but I would be fairly certain that it would fall short of 1/4s. Of course a shorter impact time is desirable, as its largely the rate at which the energy is transfered into an opponent that counts. Over the course of a days sailing, your average yaught sail must have had kilowatts and kilowatts of energy transfered into it from the wind, but nout happens in the way of damage. Focus all that energy at once (imagine some uber gust of wind) and you suddenly find youre missing your sail, mast, wrigging etc.

Im sure tooth design must play a huge factor in this- do people generally prefer the sharpish armour piercing teeth, or a bludgeoning type of tooth- Im sure that should perhaps be taken into account when deciding what is safe to run and in which arena- I would have thought that a thickish steel arena sidewall would be happier taking a bludgeoning, as opposed to a piercing, toothed spinner- thoughts gentlemen?