Braden, I imagine that it kinda depends on what you do with it. Dose tolerance would come rapidly, as with any morphine analogue.
You would take a dose probably initially to mask pain of some kind, probably during training. The opioid effects of slight detachment would also come into play w/regards to the psychological factor. There's a big difference between the effects caused by a dose to get high and a "therapuetic dose." These guys are taking just enough to numb their pain, not enough to get stupid.
He was probably on nubain (if he was) to mask pain originally so he could train harder, longer...and found withdrawl worse than taking it. I rather doubt he did it in doses high enough to cause the sleepy, lethargic effects. On the other hand, I bet he was constipated a lot .
"In the world of martial arts, respect is often a given. In the real world, it must be earned."
"A stupid man's report of what a clever man says is never accurate because he unconsciously translates what he hears into something he can understand. "--Bertrand Russell
"Liberals - Cosmopolitan critics, men who are the friends of every country save their own. "--Benjamin Disraeli
"A conservative government is an organised hypocrisy."--Benjamin Disraeli