taking the lead in a race with great competitor(s) , as opposed to to taking it when u outclass the field is obviously something u don't see quiet often .
surprisingly no one mentioned this before but the mile WR race is a unique example for a race in which 2 runners are in a world record shape (much like rupp&solinsky and the 10k AR). though Noah Ngeny set some of the fastest 1500m times that year , the race was set for elG world record attempt (which i think they both broke) and elG wasn't far from actually setting the WR but losing the race at the same time.
obviously they had great pace maker that took them around 1200m and than Ngeny had the luxury of sitting on elG for the last lap , not being able to kick beyond him. this is a testament to elG's character (and amazing fitness naturally) , being able to keep his cool despite an all out effort and fend off such a strong competitor like Ngeny in his prime.
(probably not what the OP meant but 1 lap out of a mile race is around 27% )