I recall Bill Rodger's '75 Boston which he won in 2:09.55 (PR, American record, world's fastest in '75), stopping to tie a shoelace. Apparently he stopped 4 other times for water and back then, he might have literally stopped.
Rodgers ('70), Galloway ('67) & Burfoot ('68), overlapped at Wesleyan, an unlikely place for such long distance fame.
Amazing! Was he way in front when he stopped? I found in marathons, that, if I stop for say water, I have a hard time catching up with the others who did not stop.