So after my first test fit on one of my athletes, I got

x=535

y=530

And if I plug it into http://www.slowtwitch.com/.../bar_bore_calc_X.php

I get

Input Bar-Bore Y 530mm Bar-Bore X 535mm Head Tube Angle 73Â° Stem Length 100mm Stem Angle -17Â° Stem Clamp Height 40mm Spacer Height 10mm Headset Topcap 5mm

Output Stack 497mm Reach 445mm

The athlete, prior to the fit, has already purchased a 2012 Cervelo P2 size 51. Stack 482 and a Reach of 405

http://www.slowtwitch.com/....html#Anchor-CERVELO

My question is this. Stack looks good, but the reach of the bike seems to be shorter than recommended and I already used a 100mm stem to compute Stack /Reach. So does the athlete simply longer stem?