With a few reservations, I disagree. First, the reasons you shouldn't trust me:
1) This was nowhere near double blind.
Though, to be fair, I don't know how you do a double-blind road test in real world conditions.
1) Tire pressure was very close to what I was used to when I first took these out, so it wasn't just pressure. What MAY have made a difference in ride quality, however, was the wider rim, which makes the tire a little more oval than what I'd been previously used to, and would give a wider contact point.
2) Objectively, they're lighter, and cutting rotating resistance (as well as increasing rotational stiffness) definitely nets you faster and snappier acceleration for a given power output. There's a firm scientific basis for that.
3) Measurably, I was riding faster on these wheels than I was without. I can thank Strava for that - there's a sprint segment I've been hitting on our local rail trail for a while, a half mile at an average 1% grade, where I've been chasing the KOM for about a year now. I'm not sure if you can see my previous segment times on it, or if that's only if you're logged in as me, but the segment is below:
Last year, I gradually worked my way up to a split of 1:18 on the segment, good enough for at the time 8th or so overall, in mid-October. The KOM was 1:10, so on one hand I was close, but on the other, nine seconds' improvement is a LOT for that kind of distance. I peaked there for a while, came within 1-2 seconds of my best on a couple occasions, but never exceeded that. On June 11th of this year, after a spring spent riding pretty hard, I managed to shave off three seconds. I expected to plateau there for a while as well, but a week and a half later I rented the Enves, and on a ride with fairly shot legs, shaved another
three seconds off my best, dropping me down to 1:12, good enough for second overall. There's a little bit of subjectivity here since I'm comparing the 1:15 on a day I felt pretty good with my stock wheelset to the 1:12 on a day where I felt my legs were pretty solidly blown up, but I shouldn't have been able to take that kind of time off my PR so soon after making a pretty big improvement. I'm kind of cautiously optimistic that if I take a few more days off and hit that stretch on a day where the trail is open, I may actually be able to shave another 3 off and take the KOM outright. There's also a matter of the century on the MS150 on saturday, where I added 1.9mph to my previous best average pace. I kind of don't WANT them to be faster, the egalitarian in me doesn't want a fancy set of wheels to matter, but they certainly appear to be faster.
That said - how much of the ride quality is due to the carbon construction vs the wider rim is something I don't think I can really answer for sure one way or the other. I'd actually be curious to find out.