I have a friend who is a stoner, lawyer, photographer, husband for 20+ years to the same woman, has 2 daughters educated and happily married. He says he concentrates better stoned, and that he enjoys his photography much more (he has his own darkroom, supplies, etc..). He displays his work at a big mall where I live and people pay money for his stuff.
I also know someone else who has smoked for a long time and is basically a fuck up.
What this tells me is that it aint the weed, its the person.
Just take care of business, enjoy weed, hit Amsterdam if you get the chance, and send me any leftover pot you might have.