:/ I know whatcha mean.
IMO, it's not likely to be the drug that someone who has never used recreational drugs before in his life would just decide to start taking.
I'm trying to imagine a situation that would fit the little snippets of information Haggard has teased us with:
Haggard is staying at a hotel in Denver to give him the quiet that he needs to write. He has been traveling here from his home in Colorado Springs for many years. It's far enough away from home to give that needed respite from the everyday grind, and close enough to make it an easy commute.
Haggard is staying at one of the dozens of hotels that he has tried in Denver. Unlike most people, who return to the hotel they like, he goes to a different hotel every time. One evening, he decides that his long hours of sitting in his lonely room writing have earned him the privilege of a comforting massage. This is the first time he has ever decided to get a massage, so he phones the front desk of the hotel he can no longer remember, and asked for the name of a good masseuse.
During the relaxing massage, the topic of recreational drug just happens to come up. Since Ten is pretending to be a guy named Art, he manages to pretend he also interested in buying drugs. One thing leads to another and he's buying meth from a drug-dealing, homosexual, prostitute, masseuse.