I think OP should have picked Mutai’s 2:03 low in Boston for the comparison to GK’s split. Hall is more derivative since he was 4th in that race. Noone treats Mutai’s time as greatest ever because of wind. Same should go for GK split. GK is great; Mutai was great, especially his NYC record, GK’s run was impressive but the split time is overplayed for hype.
GK is the best, most versatile distance runner right now. He probably can’t get close to track world records but he is tough to beat there and seems totally dominant on the roads and in XC.