I find that I take it easy on the way to work, and enjoy the ride. Most afternoons however, I'm stressed out from a day at the office and I want the release, so I pick my spots where I can safely hammer it, and I do. I think for each person, how you ride a given time and route is dictated by your needs and goals. ( FWIW, I don't do a whole lot of purely recreational riding these days. It's commute/transport, training ride, or race day.