The only time I've smoked in the dark was when i pre-loaded a pipe and then forgot what the tobacco was. Still enjoyed it, and usually figured out what blend it was. But yes, like Frank said, smoking involved more than just taste and aroma.
I definitely enjoy being able to see the smoke. Cyndi and I just bought a couple of recliners and set up the sunroom to a more comfortable smoking area. The lights are, for the most part, mood setting. But it doesn't take away from the enjoyment at all.