Well the guy has brain damage from a mortar attack (in addition to PTSD), so I think it's safe to say he's not playing with a full deck. It sounds like he's literally missing part of his brain.

From the article rbw posted the other day:

Goodwin said that Luc Tieman had a significant dent in his head that church members said was from a mortar attack in Iraq and that he suffered brain damage as a result. After that, he always wore a hat, she said.

"He did two or three tours in Iraq. He got injured the last time and that's how he had money. He got, like, $4,500 a month."