Had some free time with no racing so I conducted several wheel tests on the TT bike on the same strava segments back to back to back, etc. See the attached word document for specific results and further info. Strava here:

This was not a scientific test but I did no changes other than the wheels and tried to minimize variables. There were very few cars and the shoulder is very wide. Tests were over 20 minutes each and I was going 24mph+ for all of these. Road is very flat. Wind was under 3 mph. Favero dual side assiomas calibrated before the ride.

Fastest to slowest:
#1: front 65, rear 88.
#2 Front 65, rear disc.
#3 Front 38, rear disc.
#4 Aluminum training wheels

Any ideas why the 88 was faster than the disc cover? Could the Ican hubs make that big of a difference? They spin fine in hand.