Hats off to Ben Orkin and Harrison Rea for a remarkable effort. It seems as if it's only a matter of time before another group of intrepid kayakers steps up and shatters not only the Emerald Mile's human-powered record, but also the motorized record.
It seems to me the 'speed records' should be categorized. I would have a hard time putting kayakers in the top spot, when the record is held by a dory. I understand the 'human-powered' argument, but I would like to see the records hold as like-for-like. You could have something like this:
Fastest Trip Through Grand Canyon (regardless of how it was accomplished)
Fastest Human-Powered Trip
Fastest Motor-Powered Trip
Fastest Human-Powered Trip in a Hard-Hulled Boat (Or Raft)
Fastest Kayak Trip
I still advocate for taking ones' time, but there will always be someone who wants to go for speed. Congrats to these 2 guys on a very impressive trip. Seems like they hold the record for fastest self-support kayak trip.