We had a great example yesterday of the beauty of thinking in an XP (Extreme Programming) way about development.
We were making some changes to our billing system to add some improvements and flexibility around our contract billing processes. Very quickly we got into what-if after what-if and couldn't see the wood for the trees.
Remembering the KISS (Keep It Simple Stupid) principle we identified some new features required as well as some refactoring in order to simplify what we had in place.
We'll probably still have to solve some of the what-ifs we came up with but we can worry about them when we absolutely know we have to deal with them. We'll also have a cleaner and simplified system upon which to work. It's also amazing how many of what-ifs won't be issues when we come to them.
Velocity maintained, system better for it.