Actually, I have to argue the dopeyness... I used to do it everyday for 2 or 3 years when I got home from work pulling hard on that bong and to be honest I found it hard to remember things I did in the past. Just like watching movies when toked up. They'd be great movies, but don't ask me what they were about a couple of months later. Used to happen when I was at work, too (never did it before or during, though).
I didn't do the reg's (too weak), though, but crippie and afghan, ak-47, etc.
I stopped doing it a few months ago because I may be in the job market again, but I have to admit my memory is slowly coming back. Does that mean I'd never do it again? Hell no, I know I will. I don't see anything personally wrong with doing things as long as it's not in excess. What I used to do was over the top, but I can't see why it can't be enjoyed during the weekend.
The only thing that's really said is that long term use causes manic depression by the age of 30. And that only happens in certain cases, and wouldn't stop me.