So how many people with expensive bicycles end up driving sometimes, because there isn't secure storage for their bicycle at their destination?
I would disagree with you that wheels hubs and BB are the only thing that make a difference. I have to go down and up over three hills to and from work each day. I'd put the entire wheel as first place in "most important upgrade." The shifters and dérailleurs come next for me. My racing bike is a 1993 Specialized Epic Pro. The frame is on it's third wheelset and second complete change of components (last changed in 2003). After a few thousand miles, the slop in the original "105" shifters became maddening. Changing to the Ultegra gruppo made a 10-year-old bike feel better than new.when i said people who buy expensive bikes do it for the sport i wasn't considering people who spend money on the bike that really isn't necessary. as you said in your previous post, the cost isn't linear. since the ability to bike well is dependent on your fitness, the bike is much less important than your body as you begin to spend more on a frame. (there is a huge difference in what a cyclist can get out of a $300 vs $1200 bike, but a relatively small difference between a $1200 and $2100 bike, especially if you aren't an excellent cyclist). it's the same as someone who only commutes to work buying a ferrari. sure you can, but thats not exactly efficient shopping. don't get me wrong, i like my bike to have the best frame and components it can, but really, wheels, hubs and the bottom bracket are the only components that REALLY make a difference. i mean, i compete, so i know my bike pretty well, and my competition's bikes. i can say with certainty that most people purchase bikes that are out of their physical range. you don't need a carbon fiber frame when you can barely pull 20 m/h up a hill.
I also recommend. That's the fellow I just purchased, in fact.actually, for general commuting with possible off-road conditions i would recommend a cyclo-cross bike (sometimes referred to as a "cross bike"). they're designed for special type of off-road racing. they're sturdy, lighter than a mountain bike, can do remarkably well against road bikes, and because they're built for off-road, you don't have to worry about jumping curbs or rocky areas.