Like Garth, I have never had a steel frame bike break from normal use. This has not been the case with modern equipment. First the good about modern bicycle technology:
Building on a recent thread of index vs. friction shifters, I would say that brake lever mounted index shifters are one of the biggest technological innovations in recent bicycling history. I would never do any competitive cycling without an index shifting bike. Also, the dual pivot brakes are much better than most any of the old single pivot or center pulls.
Now the bad: Modern frames simply do not have the durability (or comfort IMHO) of vintage or KOF lugged steel.
I recently had a Bianchi XL EV4 frame whose head tube nearly disintegrated from multiple hairline cracks in the alloy. The solution? Throw it away. Anyone need a Bianchi carbon fork?
Another Bianchi carbon frame began to make a loud snap crackle and pop sound during one of my 50 mile daily round trip commutes. I couldn't figure out for the life of me what was going on. I kept cleaning and lubricating the chain, pedals, changed bottom brackets. I finally figured out that the bottom bracket shell was twisting and turning inside the carbon wrap of the frame material. Luckily this one was covered under warranty. Bianchi sent me a brand new frame.
The best of both worlds: I got some cheap Veloce 10 ergo shifters, a Veloce 10 crank, casette, bottom bracket, hubs and brakes. I easily put this set up on a 1978 Austro Daimler Vent Noir II chrome frame with Nuovo Record head set, seat post, and Brooks leather saddle. It rides like a dream. Weight is about 21 pounds.
The difference in weight between the carbon Bianchi and the Austro Daimler equates to about four Guiness per week.
Its surprisingly easy to fit modern index shifting equipment to an older steel frameset. For practical riding, mating the best of the old (or KOF), with the best of the new, can result in a very pleasant riding machine.
Jeff Pyzyk
Milwaukee, WI