Two nights ago a high school meet, I had dinner with one of the other coaches and he told me how in the mid 80s he got to watch Ben Johnson in a training session in Ottawa, and to this day he still is in awe of what he witnessed. It sounds like Ben was doing something like 30m block starts, and he has trouble believing how it is humanly possible for anyone to get out of the blocks and up into a running position as fast as Ben was repeatedly doing.