I smoked a fair bit of puff back in the day, although I never partook before playing -- it was a nice way to wind down after a lengthy Saturday afternoon rehearsal though.
Quick story with a bit of current relevance: back in the day we used to rehearse at Angie's in Wokingham, we'd spend all of Saturday afternoon there and then pack up & leave in time for the evening's band to load in. One afternoon we'd finished playing and were just having a chat when a chap walked in through the door -- he was in shadow so I couldn't see him. He apologised for interrupting, saying he was with the evening band but realised he was a bit early and could come back later if we wanted. We said it was fine and that we were done. "Great, thanks" he said, "oh, my name's Herbie by the way..." as he walked out of the shadows, and my mind went oh my god that's HERBIE F***ING FLOWERS and I nearly fell over myself to go and shake his hand. He was a lovely guy and chatted with us for a bit, and then there was a lull in the conversation. He sighed and said, "well I don't know about you, but I'm going to skin up..." He rolled two tiny spliffs of this ridiculous grass, smoked one himself and sent the other round the band, my god it was wonderful stuff. Herbie by name...