> Does high dissociation=PTSD?

depends on your theory of each of those terms. according to some theorists they are intimately related, yeah. some theorists think that one dissociates from stuff that is traumatic. i guess the reliving of trauma (through flashbacks and the like) could be seen as dissociating from present circumstances, too.

> I guess what I am wondering is whether PTSD starts to be used as a catch-all?

you and the health insurers lol.

PTSD was originally included in the DSM in response to lobby group pressure from vietnam war vets.

a category that was initially meant to be for people who had suffered from 'objective' and verified traumas (horrifying death of comrades, natural disaster and the like) has been extended considerably (to child abuse or to stimuli that exceed coping abilities etc).