In Olympic, I had Thomas Longosiwa, and he won bronze medal because the race WAS NOT A 400m RACE. Thomas has a high level of endurance (he comes from 10000m, and I want to go back to this event next year), but is not very fast (may be 3'37" at his best in a fast 1500m). But in London, the last 2 km were run in 4'58".
Who saw the race, could realize Thomas almost was tripped with 300m to go, lost the balance, had to slow down because boxed, and was able to go again. I think there was nothing to do with Mo, but probably, without this accident, he could look for silver.
Anyway, I didn't put Thomas in Bruxelles because I think that, at the moment, he doesn't have the specific endurance for running under 26'50", that is the only reason because an athlete having 12'49" can try the double distance. Of course, he can move to 10000 for WCh only if I see the specific training can bring him to run 26'30", otherwise there is no reason.
About Isiah, the race can give us only some info. Personally I don't think he can be really prepared for 10000m, so if able running under 26'50" he can show the possibility to run under 26'30" with specific training for next year (he ran 3000m few days ago, and clearly never went, during the last period, for long fast run or used long intervals on track).
About Nicholas Kemboi, of course I know he could run 12'53" with a perfect race during the period of Bruxelles 2003. However, he could run faster 10000m, too, because during that race, Haile, when (looking for the WR) realized that after 8 km there were still with him two my athletes, slowed down for 3 laps (from 62" to 67") losing the opportunity of the WR but only looking for winning the race, and Nicholas attacked during the last turn for a lack of experience. They finished the last 600m in 1'25", and with the 3 laps at normal pace the final result could be very close 26'22". So, for Nicholas I can suppose values of 12'53" / 26'23", meaning a difference of 37" with the double of the shorter distance.
This doesn't change the equivalence 5000 / 10000, point we were discussing, for a real specialist of 10000m.