Sorry if I offend Rob, but he's either off his rocker or he's teasing you. I have been riding road bikes for 20 years now, including state and national level competition, and in my experience, the law of diminishing returns starts way below that figure. Of course most of us WANT the fancy carbon frames with super light components and aerodynamic wheels, but those things are only NEEDS if you're being paid to get in first place at a big time race. When I broke the top tube on my very light scandium frame with Ultegra components and lightweight fork, stem, saddle, and bars (which still cost less than $2500), I was on a tight budget and settled for a $1100 Specialized Allez with 105 components, and I love riding it just as much as the previous bike. I also know people competing in elite level races on bikes they bought for less than 2 grand.
Somewhere around the 105 level, the rising costs generally equates to lighter weight (maybe smoother operation) and not durability or longevity. I think perhaps some hardcore enthusiasts such as Rob sometimes forget the concept of the term "entry level". I'd also like to point out that only 1 of the 4 bikes in his signature ever cost more than $2500.
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