rich kenah ran 1:43 and medaled and you say he couldn't run sub 50. if that were the case, he would own the mile and 3k records, because he'd have to have spectacular aerobic ability to average around 51.7 for an 800 without being able to drop 1.8 seconds in an open 400. ridiculous to put steve cram up on that list when he ran 1:42.88 on a windy day with little pacing. that's 51.4 avg. and he would close in 25 in mile or 1500m races.
Webb ran a triple in high school with 4:06, going into in 2:14 and coming back in 1:52, then a 49 open quarter and a 1:49 800m; before prefontaine, he ran 6x400m in 54 and then was allowed to open it up in the final straight of a seventh quarter, which he ran in 52. It's fair to say that he had 47 speed.