The DADT policy says that openly gay people can't serve in the military; if it's revealed, they'll be discharged. And yes, it's idiotic for all the reasons you mention, and several more. It does nothing to reduce cases of sexual assault, it hampers the trust that respondents talked about with the "critical bonding" comment, and it adds the stress of having to stay closeted to gay service people already under the stress of being in combat. (And that's bad enough as a civilian).

The issue it really serves to address is that last comment about religious beliefs and damaging the military's credibility. In other words, it serves as a punishment. Similar to the same-sex marriage bans, it gives people a chance to say "we do not approve of you." You can still put your life in the line, you can still pay taxes, etc, but we'll be damned if we acknowledge you as an equal.

And as far as I can tell, the survey went to both men and women, both gay and straight. Also to spouses of military personnel, so there was likely a higher percentage of women respondents than you'd get just by surveying active-duty people.