the person who posted that this board lacks sprinting knowledge is right on.
there is no consistency among the posts in terms of whether we're talking starting from the blocks FAT, stand-still start hand-timed, or running start hand-timed. for a 100m race, the differences between those three things are huge.
for a true FAT 100m race, i think 11.20-11.50 is a good rance, albeit a fairly large one. with practice he could probably dip below 11.00, but why would he practice it? a lot of this would depend on his reflexes at the start, something that i don't think any of us have any knowledge of.
hand-timed then would be something like 10.9-11.2.
running start hand-timed? then you're talking 10.0 or so. for context, i believe anchor legs of 4x1s have been timed in the 8.5 range. and MJ ran the last 100 of his world record 200 in around 9.2.