It was something I considered doing, but decided against. For the same reasons as everyone else, I'm sure - not wanting to take a drill to my new carbon frame.
Instead, I bought Jagwire cables that come with the internal sleeve, thinking that I could at least fit the internal sleeve in there and still have completely unexposed cables, but no such luck. I tried pretty hard to force wire with the internal sleeves through the internal routing, but never got it through. One way or another, I'm sure it could be done though. I could have sworn that I thought I read somewhere that someone had gotten the internal sleeve of a specific cabling system through the 057 frame.. Just can't remember which cables it was that they used. Either way, that may be something to consider trying.