I'd say yes to your scar tissue question, it can cause a lot of problems.
do you think your body produces excess amounts of scar tissue?

Some people seem to do that. A good dr should be able to tell , I don't know if there is a test or imaging for it though.

Dizziness, I had it pretty bad when I was still working at the beginning of my rsi/tos - I was on modified work already by then, but the dizzy spells stayed with me for awhile.
I think mine were from spasms affecting the vertebral artery.

I had all of the symptoms listed in the vertebral artery section on this page-
http://tos-syndrome.com/newpage12.htm

DIPLOPIA, DYSARTHRIA, DYSPHONIA, DYSPHAGIA
has to do with vision, voice, speech, swallowing - might not be in the right order but I was wondering if you had any of those sx also?