i meant absurd in the sense that i would never be forced to walk with my bike if i didn't want to. yeah, if i got a 3rd flat on my commute and i was only 6 blocks from home, i'd just walk 10 minutes and be home instead of waiting for a train/bus or hailing a cab. but many of the other commuters in this thread say that it's necessary for them to carry a pump as a back-up in case they burn through their CO2 cartridges and are forced to walk the rest of the way to their destination. in chicago, the notion that i would ever be forced to walk with my bike to a destination because i ran out out of CO2 is absurd. there are ALWAYS other transport options that can fill the gaps in a pinch in a city like chicago.