One of the best parts of commuting, for me, is my reduction in stress. I get exercise (which is important, since I pretty much sit at a computer for 8 hours), get fresh air, and don't have to fight traffic. Adding time trials to the commute has no appeal.

I take it pretty easy in the morning, push a little harder in the afternoon and save the hard rides for the weekend. But, I have never been a racer at heart.