I used to keep detailed notes on each cook-- times, temps, weights, vent settings, turnings, mops. Once I got to know my cooker and the different meats I was cooking, I stopped. Chris' cooks detailed on the site demonstrate such logging. I'd be willing to bet-- and he will probably tell me I'm wrong-- that he doesn't so log every cook anymore, either.
I view it as part of a learning curve. While you're in the curve, it's great to have a previous cook to refer to, and to compare. I think once I got the temperature regulation thing down, that's where I stopped the every-fifteen-minutes detailed logging, and just kind of kicked back and enjoyed it, knowing I was going to produce the desired outcome.
Now, if it's your desire to cook competitively, I'd say log away. That's the alleged secret to competition-- knowing what weight, what temp, what time, what rub ingredients, what sauce formulation, and, obviously, what outcome. Having that in a database would be invaluable.
