I had a number of conversations with a musician friend about drugs and bands. He was pretty adamant about staying sober and clean while playing in a band, and his main reasoning was that when you're stoned or high, you just don't know when you sound like crap. When you're chemically altered, you always think you sound good.

I've worked as an ER/Critical care nurse for 15 years, and I can say that categorically that all the stimulant using patients I've cared for tend to make bad choices. Perhaps it's a selection bias and only the people on stimulants that make crap decisions come and pay me a visit in the ER.

Do you really want a substance clouding your judgment when you're working on your startup? When you're chemically altered, how do you know that your business decisions aren't crap?