> And you're kind of confirming my original thesis, that its a class of drugs created by the ruling class for the working class to make the best workers for capital/ruling class, which it seems to have accomplished that in your case...

I don't take amphetamine specifically, methylphenidate, which seems to have no pronounced influence on the apparently correlation based study outcome. Taking these drugs however is not something I approach lightly, but it's also not something I do for anyone else. If anything, it helps me maintain my own adult life. The job is an incidental but important factor.