So I ambled over to the KM store in Mountain View, picked up a quart of the stuff and a narrow roller on a long handle and came home and got to work. It took about an hour, but the amazing thing is that the old and new paint blended perfectly. You can't see that anything happened unless you really know exactly where to look. This is particularly impressive given that the wood part of our house faces west into full sun, and we last painted when we bought the house almost 5 years ago.
So big ups to Kelley Moore.