I had heard 2nd hand that when Katie Compton had signed with Trek, she was not happy at all with the Cronus and had the Trek guys scrambling through warehouse for old XO frames which got repainted in time for her to finish 2012/2013 with. These were supposed to be the basis for the new Crockett and Boone designs (yeah, sans IsoCoupler stuff). Just rumors or is there some truth there?
2011 xo2 geo
Pretty similar to my 2008 XO2... what's old is new again...
Crockett has more relaxed head angle, longer chainstays, taller headtube, longer wheelbase, etc. Based on comparing the 50 to the 50.
Trek has an in-house fabrication shop and a few full-time framebuilders/machinists/fab guys on staff. They might've used old-stock tubing drawn for past models to build the prototype crocketts that KFC was riding last year, but it would take so little effort for trek to build something custom that it's incredibly unlikely they had her on an XO.