I am a commuter, and while I do carry tools, I have no interest in repairing my bike on the side of the road. I leave myself only enough time to get to work, so I wear my office attire on my bike, and I don't have the clothes or time to repair my bike on the road.

My bikes are extremely well maintained, and I run puncture resistant tires so I very very rarely have a problem. On those rare occasions, I lock up my rig and take the nearest bus the rest of the way. Then come back later and repair my bike when it is convenient. I have only had to use the bus once so far this year, and I was able to pick up my bike with my wife's car and repair it in my garage.

This may sound ridiculous, but after 6 years of commuting every day I have found this to be the best use of my time.