would have to say that he is almost positive that heroin
would be destroyed by the heat of the cigarette ember. That would be why people have to vaporize it on tinfoil in order to smoke the heroin properly.
However, somewhere on these boards (can't think of where, it wa a while ago) someone mentioned that although they were aware that the heat would destroy the heroin (Swim believes it was cocaine
in the post he is referencing), they believed that it still produced an effect. They believed that as the cigarette burned the ember would vaporize the heroin right below the ember. Sorry if that doesn't paint the best picture but it was the only way he could figure out how to word it.