Yes, I like Joe, but these HM results are concerning.
The main problem is that it seems that the idea that he will get better as the race gets longer is just not true. Someone mentioned he's big...that may be it, but really the reason is irrelevant.
The facts are that in a 5k time trial he ran 12:54, and despite a slew of people doing it in the last few years, he could not break 27 in the 10k. His 10,000m was 27:07, yet he could not break 61 minutes in the half. When you compare with peers with similar times, he underperforms in longer distance.
I think people have assumed that because he likes to run his easy runs (too?) fast, he will be better as the race get longer. But based on his results, he gets worse as the race distance increases beyond 5k. This may be a case of thinking that moving up is the answer when you aren't fast enough to compete at the shorter distance, but in reality that is your best distance.
Finally, I just don't buy the "this was the first one, I need to figure out the distance". It's running. You just find a pace you can hold and run as fast as you can. You are either fit enough or you aren't.