First, I knew you would avoid answering my questions. It is standard reaction when someone is in denial. Second, an answer to the above question is irrelevant. By example, can you point me to evidence that problems with guns is bogus? Can you point me to evidence that problems with surgery is bogus? Can you point me to evidence that problems with aspirin is bogus? Can you point me to evidence that problems with eating dairy foods are bogus?
Your lack of applying logic to the use of drugs in indicative of someone that is in denial, deluded by some factor or belief or inability to process information in logical way.
As for your next round of questions.. the answers are No, No, No, and No; though of course it is assumed that misuse of the items is not part of the question.
I proudly state once again: that I am inclined to believe that mind-altering drugs can cause problem if for no other reason than misuse.
I just noticed that we posted replies (above) at exactly the same time and I was about to post the "great minds think alike" thing then I realized that you'd be insulted.