He didn’t talk about foot placement on the blocks and i find nothing in the book on that topic. I guess 99% use about 45° for front block and higher for rear block, this is not specific to Asafa. As for feet high up on blocks, well i’m not sure it is for greater stretch reflex as Asafa uses the same placement wether the block pads are short or very long (like it was in golden leagues). I guess it has more to do with the drag foot he uses before the landing of the first step out of the blocks.