Forget the tire irons. Get yorself a Speed Lever. Can't vouch for its effectiveness on high-pressure skinny roadie tires, but on my mountain bike commuter, it is fast fast fast and so easy.
http://www.bikeworld.com/components/...pid=772&cat=17
Easily the best accessory I've bought for my bike.
I run a thin little double-ended cable through the seat bars and onto my u-lock. Could be cut, but who's going to bother with tools for a seat? (he asked hopefully)