Realistically, I doubt there's anything else he can do - that the President would find politically acceptable, that is. He could probably sustain twelve-on, twelve-off tours if the entire Army Reserve was mobilized and the full Army National Guard was federalized. But that'd almost certainly kick off a firestorm politically. Similarly, he could keep twelve-on, twelve-off tours if the President could get our "coalition partners" to chip in a bunch of combat-ready brigades - not that there's any chance of that happening.

I suspect that fifteen-on, twelve-off is the least-damaging thing that Gates and his staff could come up with. That is frightening. In his shoes, I'd be really seriously thinking about resigning rather than be the one to grind the Army further into dust.