How many deployments are "too many?"

There's another article about this that I saw this morning: http://usnews.msnbc.msn.com/_news/2012/03/29/10927433-afghan-massacre-sgt-bales-case-echoes-loudly-for-ex-soldiers-on-hotline-for-vets

It makes my stomach hurt to read that soldiers are being recycled back into battle so soon. One stand-out quote in the article:

In an evaluation after his first deployment, Cordova said he answered 'yes' to most of the combat-related questions: "Yes, I saw dead people. Yes, I saw dead Americans. Yes, I fired my weapon. Yes, I killed Iraqis. Yes, I killed the enemy. I didn’t report that I was a threat to others, but I put that I would like to speak to somebody," he said. "What did the Army turn around to do? They just overlook it. Four months later, I’m in Iraq again."

Based on this article, it doesn't sound like the soldiers are being properly evaluated upon return. If they're not being properly evaluated, then they're missing a lot of people who may need help dealing with PTSD.