No, you believe the Dimond will be slower. Belief is not knowledge.
Sure, but that goes both ways. Rappstar, above, says, "Based on what I've seen, the Dimond is faster than the Shiv." But then doesn't explain what he's seen - just offers justifications for not explaining it. To his credit he did water down the claim in the same paragraph, "But for me, I believe the Dimond is faster." (emphasis mine).
Most consistently, it's been on my measured TT course. Speed on that course - which is a rolling course with a net ascent that is relatively sheltered from the wind - is higher for a given power output on the Dimond than on the Shiv. And that's reinforced by a lot of rides on a lot of the same roads over and over. As I said, there are a LOT of variables. I have not made an effort to isolate every one of them. For example, the Dimond MIGHT simply be faster because 1X is faster than RED22. Or because the Dimond does better at low yaw relative to the Shiv which was admittedly designed (rightly or wrongly) for high yaw, which I rarely see where I train.
Before I signed a five year contract with Dimond, I talked to David Morse - who I knew from Zipp and who largely designed the Dimond and who is now back at Zipp - and several other of the Zipp engineers who were a part of the Dimond project (many of them contributed their time/expertise to helping "revamp" the Zipp 3001/2001). And I've continued to talk to them since as many of them have put the bike into the tunnel.
In terms of "explaining what I've seen," I wouldn't say that it qualifies as highly empirical. I did not take out both frames and "Chung" them with identical (or as close as possible) set ups. I've just seen, consistently, that I go faster on a given power output on the Dimond than on the Shiv. This isn't from "testing." It's just from riding. I don't want to present riding as testing, but I also don't want to discount that things can be apparent when you spend enough time doing it... I promise I'm not trying to be deliberately obscure here.
"Non est ad astra mollis e terris via." - Seneca | rappstar.com | Facebook - Rappstar Racing | @rappstar
Ask me about: DiamondBack Bikes | Zipp | 1st Endurance | Normatec - $100 off RAPP2017 | Quarq | SRAM | MatchRider | Kiwami | ROKA