OK, just gotta chime in quickly. I scanned the RW thread and nowhere in his writings did I see the OP ever state that this sub-4 attempt (success?) came in a mile run. It is heavily implied, but nowhere is it explicitly stated. Even splitting 59-high could mean for every 375 meters of a 1500 ... or every 200 of an 800. I just noticed this because I was thinking, hey, I could go sub-4 right now for four laps of a 200M indoor track. Then the guy never says "mile" so ...
Of course, I skimmed quickly, so maybe I just missed it.