As modern neurobiologists point out, the repetition of the traumatic experience in the flashbacks can be itself re-traumatizing; if not life-threatening, it is at least threatening to the chemical structure of the brain and can ultimately lead to deterioration. And this would also seem to explain the high suicide rate of survivor, for example, survivors of Vietnam.
There is clear evidence from internal investigations in the past that some raters actually see themselves as adversaries to veterans. If a claim can be minimized, then the government has saved money, regardless of the need of the veteran. Just recently, the press exposed an official e-mail from a high-level staff person who stated in essence that PTSD diagnosis was becoming too prevalent and offered ways to delay and deflect ratings in order to save the government money.