I don't think that a Red tailed Boa (even a big one) could have the strength to wrap around and choke you with out you being able to unwrap it, especially in this case where there WERE other people around. It makes me wonder if the guy had any other conditions that led to this, maybe asthma or something that would have made it difficult for the guy to breath anyways? Just a theory but this story seems suspect to me since from what I could gather from the story, his roommate, roommate's girlfriend, and sister were all there when it happened.
Were drugs involved? how come nobody pulled the snake off him?