Thanks for posting this.
I run plenty of hard trails, and I'm not particularly fast, so I respect the good trail runners. I mean no disrespect when I say that elite marathoners for the most part could win ultras, if they wanted to.
Mostly I think it is funny when ultra defenders get all indignant about how different they are. As if Ryan Hall, Deena, and Meb aren't doing long runs in the mountains at Mammoth. But somehow some of these ultra defenders get to thinking they are the only people that can run a trail. Yes, 100 miles requires a lot of training and a mindset few have, but speed matters. Yes, running a lot of vertical is challenging, but the fast guys can do this too.
One reason the EA runners are so good is they run hills at altitude every day on dirt. That's why it is laughable to me that they couldn't excel in trail ultras. Sure, some of these guys may be too brittle, but not all of them are.
As for the Africans showing interest in typical trail ultras, I don't think it will happen on any sort of scale. These races are not conducive to large fields. Large fields drive purses, unless a sponsor sees a good market opportunity. Maybe this is possible, but I have my doubts.