Just in Flagstaff, Diego Estrada ran 4.04.36, altitude converted to 3.55.48. Looked amazing, he had a good rabbit until about 1150m.
Estimated splits:
62 (109)
204
305
404
http://www.nauathletics.com/sports/track/2011-12/files/Mtn_T-s_results/Men-s_mile.htm