There's no way to put a limit on what one may accomplish individually if the intent is an impeccable intent. Don Juan's teachings are not spiritual. I repeat this because the question has come to the surface over and over. The idea of spirituality doesn't fit with the iron discipline of a warrior. The most important thing for a shaman like don Juan is the idea of pragmatism.
There's no way to put a limit ...
Quotes from the same author
The trick is in what one emphasizes. We either make ourselves miserable, or we make ourselves happy. The amount of work is the same.
“We choose whether to be warriors or to be ordinary.”
“A warrior seeks to act rather than talk.”
“A warrior lives by acting, not by thinking about acting, nor by thinking about what he will think he has finished acting.”
“A warrior never worries about his fear.”