I don’t recall Charlie saying that, but I do remember him saying that you don’t run 6.32 splits by holding back (John Smith style), and I think that gets into why all of such “expert” projections are always wrong. How they get to run those 6.32s without holding back is all the 400-style overdistance that the top guys are doing now. Just like people couldn’t see going much faster than Mo’s and Ben’s 9.79s before Asafa did it, we can’t see going much faster than Bolt’s 9.58. But just like Michael Johnson’s “untouchable” 19.32 has been well exceeded, so will 9.58. We just can’t see how it’s going to get done yet.
Remember that before Bannister’s four minute mile, there were scientists saying that the human body cannot run a mile in less than 4 minutes.
Training is not static. New methods come out that build on old methods.\
Would Bolt actually go slower if he managed to figure out how to come out hammering out of the blocks? Or might he actually be able to go faster by placing more emphasis on 400 training so as to have more speed/endurance reserve (see Flojo)? I don’t know, you don’t know…and a professor of mathematical sciences doesn’t know either.