Thanks everyone. It’s great to get intelligent feedback.
I agree with CF that we should use drills that suit our aims or needs. I was chatting with a very good coach last weekend about drills. He uses a few and his athletes do them at miraculous speed. I had my own athletes do a handful of drills (none of Mach’s As or Bs), but ones which I felt put the athletes into positions I wanted them in. I also wanted the warmup to be relaxed and not induce undue tension (not that Mach drills aren’t done in a comfortable, easy way). The only thing I was ever interested in was the quality of contact which entailed the position of the whole body at the moment/point of contact. This pretty much entailed achieving Triple Extension or close to it at the moment of contact and maintaining T/E and a straight line of force through lift-off. And all of it was done with the minimum of tightness (for want of a better word). There was of course tension/stiffness through the core and the supporting limbs, but not up in the neck/shoulders/arms during the drills.
The position was paramount, speed could come later in the training session through cranking up the rhythm, in my opinion.
But there seemed some doubt from this coach and many others that you could produce a world class result unless your athlete could perform the drills at world-class speed.
Maybe my way of doing things works fine for 400m runners, but not for 100m sprinters.
It would be interesting to know what Bolt does in the way of any drills for motor patterning, or whether what we saw on the video posted by Niko is the whole story.
The point of drills is perfection through separation into parts. trying to ddo them at great speed defeats the purpose most of the time because they become tight, technically poor, with shortened ROM. In short, everything you started doing the drills to overcome in the first place.