Interesting to see it studied. To really answer the research question that was posed, though – wouldn’t you have to look at whether the same athletes ran faster when taking quicker strides, or faster when taking longer strides?
Seems like there are a lot of other variables (Time of year, What the competition was like, weather, etc) as well. I can only think of a few sub 10 guys (Montgomery is the only one immediately coming to mind) that took as many as 50 strides over 100m – and most of the sub 10 guys are down nearer 43-45.