^^ This was right. I had an LBS swap my cassette's: 9spd Ultegra to the Shimano wheels and 10spd 105 to the Aksium. I also swapped the stock Selle San Ponza for my Specialized Alias 143 and took the bike out for my regular 40km loop. Avg'd 26km/h, max 54km/h, keeping in mind these speeds are through the core of downtown Toronto, with the max occurring down Kingston rd, between Beech ave. and Queen. On my OCR2 I was avg'ing 21km/h, so the Cannondale is a pretty substantial improvement. I can only explain the improvement by feeling of complete power transfer from the BB to forward motion. Also, the wishbone curve in the seat stays is an excellent shock absorber.

Advice to anyone looking at the CAAD9 Optimo 3: have the LBS upgrade the stock wheels to at least Aksium or Ksyrium Equipe. The stock wheels are junk.