Well ho ho ho, I also have been reading (where?  Compassionate Mind?) about how those one-size-fits-all relaxation and mindfulness exercises can make anxiety worse if done the wrong way.  If you have PTSD, the symptoms might get worse if you try to make them relax, they'll be even more scared that something bad will happen and fight you on it. PTSD is there to protext us, and it's not going to go away in a yucky community agency room full of strangers asking us to let down out guard. So those moron social workers leading anxiety support groups that I always walk out on in the first meeting are... morons.  Again, some science to back up the feelings.  We ARE right about what we feel, and the scientists who are paying attention know it.