Speed endurance the key to *all* 11/12second sprinters?

That is an option, especially if speed work is on the grass though I might be inclined to go FEF, FEFEF, and back to FEF because as you go farther into the program the other speed work becomes more demanding and would compete too much with FEFEF. This is of course is related to sprinters and Bo’s protocol would be more amenable for jumpers with shorter distance speed requirements.