Originally Posted by meanwhile

This is technically true, but in practice usually isn't. Because

1. A frame can't absorb nearly as much shock as tyres - and buying better tyres with a higher TPI is cheap compared to buying a CF frame

2. CF frames that flex out road shock but transmit power well are much more expensive to construct - you need to use different types of CF in different parts of the frame with complex weave orientations, some of this CF is a LOT more expensive than the basic stuff, and the price of construction goes sky rocketing. Very few CF frames are built this way. More typically Trek or Spesh use the cheap CF and simple construction, then put a better tyre (and maybe nicer grips or bar tape) costing a few bucks more on the CF bike. The punter rides it and thinks that the ride difference is due to the CF frame and parts with an extra $500.

If you want to improve ride comfort without losing speed, spring for premium tyres, don't over pressure them or go too narrow (both will make you slower as well as less comfortable Tech FAQ: Seriously, wider tires have lower rolling resistance than their narrower brethren - VeloNews.com) and using two layers of good bar tape. Or one layer and some gel.