In case you live under a rock, Damon rinard is one of the senior engineers working for cervelo. he arguably holds as much clout as gerard vroomen and phil white in cervelo, the founders.
As a leading company in aero bikes, I think cervelo has done their due homework. if you are serious about buying a fast bike, some basic research will show you that cervelo does wind tunnel testing. alot of it. not only of their own bikes, but their competitors bikes. there are pictures showing them testing the S5 alongside it's contemporaries the specialized venge, and the scott foil. in the design of the P4, a simple search on slowtwitch will show you cervelo's own data HERE:
http://www.slowtwitch.com/...the_Tunnel_1929.html . as you can see, the Plasma 3 does exceedingly well in the tunnel at 10-15 degrees.
obviously the P5 and other bikes like the BMC TM01 haven't been tested as they are relatively new, but if a senior aero bike engineer who HAS tested the plasma 3 in the tunnel takes the time to reply this post, and repaetedly praises the merits of a COMPETITORS bike, I think I'd pay abit more attention to what he has to say. I don't think damon would reveal any test data cervelo has done, company secrets and all that. But I'd suggest you be more appreciatve of good people who take their time to share their comments.