Originally Posted by kbarch

I wouldn't say a few hours, I'd say a few sessions; can't imagine being able to accomplish in a single session - no matter how long - what's taken several sessions over the course of a couple of years to refine. If one isn't an experienced rider to begin with, one likely doesn't know oneself what it takes for a bike to fit, and one may leave a fit session thinking the bike feels right, only to discover down the road that it's sub-optimal or even problematic.