Rock'n Rod
It took 72 days to start peeing yellow again, after 15yrs of daily consumption. At about day 50 my game really started to come up a notch.
Few people realize how long it can take you to pass a whiz quiz if you are a heavy pot user. I had a friend I'll call Rock'n Rod cause that is what I always called him.

Rod was and is as far as I know a 1000 ton boat captain.
When dope testing got common he couldn't pass the test. Two or three days not smoking, no go. Two weeks no smoking, no go. Six weeks not smoking, no go. Rod was frustrated and asked the doc how the hell long did it take to pass the whiz quiz?
"How much do you smoke?"
"All I can get!"
"Somebody like you it may take six months to pass the test."
Rod eventually went to work for some folks that didn't care. The personel man looked at him and said, "I know two things about you, you can pass the physical but you can't pass the drug test."
Rod told him, "I can't pass it on the way out but I can pass it on the way in." Good enough, he was hired. Another pot smoking captain I knew made a little honest mistake, he mistook a three hundred and some odd foot supply boat for a lily pad in fog. Could happen to anybody I guess but more likely if you are a little casual about your job.
Speaking of casual about your job, how many people have lost their jobs because they couldn't give up the use of "nonaddictive" pot? At least one of the operating room engineers at a nuclear plant lost a very well paying career position because he tested dirty for pot three times over several years. The first time he was warned and suspended from his duties for six months, the second time he again escaped the hatchet, third time was the charm. A hitch or two in the nuclear navy, over a decade in the nuke plants, then he had to find a new occupation. It's been years and I forget what he took up but it didn't pay but a tiny fraction of what the nuke gig did. Of course I support his firing, when things go to crap an operator may have seconds to make a decision. With the nuclear containment building in sight from my home I want it to be the right one!
I have buried several people close to me that made gross errors in judgment while under the influence of pot. That makes me a lot less tolerant of it than I might be despite smoking a bale or two of it in my youth before I saw these things happen. I think JoeyA nailed it though, perhaps the greatest harm it does to society as a whole is robbing people of ambition and motivation. How much productivity does pot cost the nation? Every one of us pays for that one way or the other.
Back when working in petro-chem plants was a white male anglo-saxon occupation almost exclusively I worked with black, mexican, and female partners without complaint, all I required was that they be able to do the job. I was one of the few that would. I wouldn't work with a pothead as a partner, too dangerous. Accident prone and just not alert, they endangered their partners. One morning long before drug testing I had started work while my partner and helper were burning one. I had my head down working while they smoked and ignored them when they started talking about a pretty green cloud they were digging. Figured they were being silly or trying to jack with me. When I finally climbed up to where I could see after a few minutes of them admiring the "cloud" I saw a chlorine plume that was so dense it looked solid almost on top of us, less than a hundred feet away. I hollered "That's chlorine you morons!" and took off at a good trot crosswind on two 4" pipes sixty feet in the air. The clowns started wrestling with each other fighting over who would be first to climb up to an opening in a caged ladder to climb back down through the chlorine. They spent days in the hospital, I never drew in a whiff of chlorine. Even when I smoked pot I wasn't dumb enough to do it on the job.
When I owned businesses I didn't drug test. However when I hired someone I told them on the spot that my insurance wasn't valid if they got hurt while under the influence, simple truth. I required that they came on the job straight and sober and stayed that way until quitting time or it was a quick ticket to the gate. The rest of their lives was their business.
Maybe the title of this thread should have been "Cannabis, pool, life, and death" Decades later it still sucks thinking about the otherwise very intelligent people I buried who made bad decisions while under the influence of pot. Most of the time I take a pretty neutral position about pot. As I typed this post I thought more and more of the harm it has done to friends and family. At the moment I'm wondering why the hell I'm so tolerant. I support the death penalty for anyone possessing an amount of any illegal substance that is obviously for resale to mess up other people's lives, that includes pot. I wouldn't be upset if it included alcohol and nicotine too. I'm tired of people making fortunes off of other people's misery and foolishness. The big bucks don't come from the occasional recreational user.
The dope dealers we need to get aren't the peons at the bottom but the big boys at the top and middle. Many of those in the middle are otherwise legitimate businessmen or wealthy people with a cash flow problem. A dirty secret we don't admit, kids from poor neighborhoods don't become bigtime dealers overnight if at all. Cut out the big profits for the big dealers or make the risk too great and we wouldn't have to worry about the little dealers and users.
Wow, would anybody believe this started out to be a short and fairly light post about how long it takes pot to clear a heavy user's system?
Hu