I don't really have any expertise, but since no one else has responded, I'll just chime in with what I've read and heard from other bodyworkers (PTs, LMTs, DCs, DOs).

I've never had ANYONE tell me that I'm supposed to have trigger points. There's a school of thought that too much static stretching can be bad for athletic performance, and maybe that's what your PT is talking about. But when the fascia is knotted, ropy and desiccated, I've never heard from anyone that it's supposed to be that way. When the fascia can't slide freely, it pulls the muscles and bones out of alignment all along the kinetic chain. You probably notice how you don't have to fight as hard to keep your feet aligned after rolling out your hips, right?

The only two "bad" things I've heard about self myofascial release are (1) not to overdo it - if you have a lot of adhesions and/or long-standing trigger points, it can be better to work them out a little at a time than to cause so much microtrauma that it takes more than a day to heal; and (2) not to think of it as an excuse for not correcting the misalignments that led to the trigger points to begin with.

HTH - just my thoughts after LOTS of bodywork and reading since my injury 3-1/2 years ago -