Most people on this thread are not accounting for their hindsight. We all now know that Chelimo was not going to retake the lead, even if the pace slowed enough to let others back in the race. We didn't know that at the time.
Obviously from Kincaid's perspective the best outcome is a top 3 finish with the WC standard. Once he was handed the lead, he had two choices: continue running sub-PR pace with two clearly superior athletes on his back. This has the very big risk that he would implode.
Or he could slow, gather his resources, and wait for either: a) Chelimo or Lopez to take the pace back over, on the assumption that they would not want the pack to catch up, or b) once the chase pack catches, somebody else would start a long kick early enough to still get under the standard. This has the risk that neither happens.
Which risk was higher? Without hindsight, who the hell knows. What can we say with some certainty? If Kincaid kept running 65s and 66s once he was forced into the lead, the odds that Chelimo would retake the lead were very, very low.
Also, with regards to the criticism that he should have been out chasing the standard prior to USATF. Look at Shannon Rowbury. With the benefit of hindsight, it seems like a mistake for her to have chased the standard. She would have been better off training! She would have had a better chance at making the worlds team by hoping the pace would be good enough at USATF, and it was! Why was she out running a hard 5K two weeks out! What a bad decision! (For the sarcasm-impaired, I'm saying this facetiously.) If Kincaid had been out racing in the month leading up to USATF, there is the risk that he wouldn't have been as ready as he obviously was. Nobody except his coach and the athlete himself have any idea how to measure this risk.