I'm against the smoking of things.
Cigarettes will kill you, weed effect you head and often gets you trying other crap, and smoking anything is putting chemicals you can't really account fro into you and allowing them to alter your stat of mind which alters you regardless of if you'll admit to it. I tend to not care if people around me smoke weed but lately I have started to care cause I get a contact high and it screw them up.
Its complete bull that weed makes you play music better. It just makes you think you're good while you play so very terrible.