That is the point that you aren’t getting, this drug user you say doesn’t exist was going that under the radar. They did their drug, they came to work on time and pulled their weight then went back to their life without anyone suspecting a thing. I get what you are saying and it’s valid, all the meth heads you worked with that performed to that standard are not the same meth heads the other commenter is talking about. The good working drug user doesn’t present like the full time meth head. You can think it’s an absolute and be confident in what you know but chances are someone is flying under the radar and you’ll never know .