I never done a 100 mile race before and not sure I ever want to(I don't think Bekele would be interested). I do think about it literally sometimes though, about how I'd go about it. My easy pace runs are about 7:20/mile and I do them for about 10 miles. I think for 100 miles, I'd get a pair of zoom vaporfly's. Them would make me be able to do at least 10 miles of the 100 miles at that pace. I would probably first do 10 miles at 8min/mile. 10% complete and pretty easy pace.
I would increase to 7:45 pace for next 10 miles. Nice and easy, already 20% finished.
I would be conservative and do 10 at 8:15 pace then. Slow and easy, now 30% done.
I would do another 10 at 8. 40% done.
I would then do next 10 at 8. half done.
I would then do the next half slightly faster, and evan try a 10 mile split at 7:15(hard to predict how you will feel later on, and what pace you will want to run at). I have good endurance and am strong so a sub 13 will be on the cards, if I eventually done it in a few years. I'm far from elite, but no elite ever run 100 miles anyway. Bekele never done it before. He would be under 10 hours if he was interested.