I think that you maybe off a little on this, not all anxiety is from gad but you also must look into the other medical aspecks of it both chemical and cns of the brain, granted the primal instinks(sp) such as anger may help stop one from thinking about the anxiety and panic but once the anger is gone you still find oneself back in the hole of lifes stresses that had started the anxiety in the first place of the recurrents of a traumatic experience and the mind and then the body responds to it with p/a's just from the sudden onset of intence fear or impending doom that is manifested in the mind, some may be able to control it to a point but for some there is a medical problem that causes them to acure and as of yet I have never seen or heard of cure for it.
I feel that for some it is like alcohol addiction just becouse one stops drinking alcohol and go's to AA and feel like they have won only to be put into a stressfull spot and thing ok just one drink will help, it's the same with anxiety it tends to wax and wane for some while others are in a consent state of fear and it becomes quiet disabling.