Hello folks!
First time posting here. I was searching for some info on this particular subject and found this thread so I figured I'd relay my experience which might help some people. First let me say that I've always had a tendency to lucid dream from time to time. I haven't trained myself to engage in it willfully, although I intend to do so, however I know a technique that has made me dream lucidly with a high degree of regularity.

Most of the time, I'm a habitual pot smoker, a couple times a day and definitely before bed. From my experience, I can only speak for myself here, I would say that marijuana negatively affects dream recall and possibly the ability to become lucid. When I'm smoking regularly, I hardly ever remember my dreams.

However, if I've been smoking daily for about 2 weeks or more and stop abruptly, within 3 to 7 days I will have 1 or 2 nights of intensely vivid, often lucid dreams. I have suddenly stopped smoking like this dozens of times and the pattern is always the same.