Let's not forget that the NYC half went out in 5:02, when it should have been more like a 4:35. That right there probably would have resulted in Mo, Geb, and Rupp breaking an hour. Granted, the half is a lot different from the marathon, but with this Rupp definitely has a shot at beating Hall if he really goes all out at OMT. Hall did break an hour once but that was quite a long time ago and he hasn't shown anything like that since. His Boston race was impressive but the conditions that day were more than ideal and he it's not like he was even in the top 3!
As far as Rupp's 26:48, that is flat out the most impressive achievement in US distance running history. However, it discourages me even more about Americans' ability on the world scene. Come on, he set an American record and got THIRD in the damn race, and got flat out destroyed on the last lap. That's the only thing holding him back, is being able to pound out a 54 when everything hurts. My advice to Salazar is to have him run 400m or 800m ALL OUT after every workout he does. Rupp's sprint speed is very good, he could probably break 11 in the hundred, but he just falls apart after 4600m or 9600m in a fast race. I'd like to see an interview with him about his plans for OTM.