I've never done it and I will never do it. Having said that in the past, I have shared a drink or two of wine (and or Vodka) a few times. I don't do that anymore either. I concluded that although under the influence the session was INTENSE, I had a hard time recalling the finer details of it. I enjoy the after buzz of a session. I want a session to stay with me for a long time. Personally speaking, wine or vodka don't allow it.
On the flip side, I KNOW for sure that atleast FOUR SP's had smoked grass before the session with me. No matter how thoroughly you use the mouthwash, the smell stays in ur lungs for a veeeery long time and frankly, I found it a turn off. I don't care if they have smoked to get in the zone. I understand why some girls would smoke weed before a session. It's a tough job and I guess a few puffs help them relax.
So as far as I am concerned, now my session are free of any stimulant, and I can only hope that (no matter what she smokes) my dance partner's respiratory system doesn't smell of it.
T8E