Isn't that why he cross referenced the obituaries with the CDC statistics? He said they matched.
I have no idea whether this man's work is legit or not. Nor do I really care. It shouldn't be a huge shock to anyone that men who regularly engage in anal sex have health "issues".
If you parse what this misleading article says, you find that the CDC statistics are saying something completely different.
I think this whole thing can be summarized pretty simply: Gay men get AIDs at a higher rate than the population as a whole. Therefore, the average life expectancy for gay men, as a group, is going to be lower than the general population. However, this does not say much about the life expectancy of gay men who do not get AIDs.
So, if someone wants to argue that AIDs shortens life expectancy, that's a pretty big no-brainer. However, that does not really say anything about whether or not homosexuality, in of itself, lowers life expectancy.