I am a child of the 60's when pot or hash was given out like candy, so I've smoked heavily from ages 18 to 42....I drove a taxi in NYC when I was in college & smoked 3,4,5 joints a day while doing so....Never had an accident or ticket....
I played sandlot football for years with the whole team stoned on either pot, hash, or speed....We didn't have great teams, but we didn't care....LOL....
Later on I was a very productive insurance salesman where I did a lot of driving & most times I was stoned by a few joints....Sometimes I worked with a partner who also smoked & we were known in our office as Cheech & Chong...LOL !! again no accidents or tickets....
As far as if pot impairs a person, I would think it would depend on the individual....
And btw I changed my stance on whether marijuana should be legalized, I now don't think it should be....
Now that you don't smoke it anymore. :lol:

