Hesch obviously is a decent runner, but if his half marathon record (~9 % slower) and even his mile record (~6-7 % slower, not sure how reliable his road mile times are) are so far away from the World Record times, I wouldn't describe him as an "international class elite". The NYT-article emphasizes that he specifically avoided competing against the elites and his winning times of 2010-2012 aren't really that impressive even with a few sub-1:05 half marathons here and there:
I disagree. His listed 2:21 marathon PR would put him the top 40% of the starting grid of international elite division of the 2012 Boston Marathon. His 3:58 mile PR is nothing to laugh at - converting that time to the 1500, it just a few seconds off the "A" standard.
The description of his performance improvements also raises eyebrows, because the mechanism doesn't sound anything like a textbook example of the mysterious "O2 vector"-doping where the boost is almost instant.
C'mon, he's not doing BBs like the cyclists are doing on GT rest days for an instant boost/recovery. Though he doesn't give the dosage he was using (just his weekly schedule), I'm guessing that with the ~18% boost in Hct he said he experienced, it's probably close to the dose & duration used in Durussel et al (~17% increase), where the test subjects after 4 weeks usage experienced a ~6% improvement in time ran on an indoor 3k TT (it sounds like he maintained his rocket fuel-induced crit for a couple of years).
My key source on Hesch is the website below, but if you have some better insight on the matter, please feel free to inform us.
I used the following site. His listed PRs for the 5 & 10 are several seconds faster than on the site you've provided. His half is about the same. The 2:21 marathon is also listed. He has a 3:50 road mile PR listed (Austin), but that would have to be on fast descending course?