My PT did not mention anything about thoracic mobility exercises either. Book also covered chin tucks and shoulder rolls but it didn't stop there. These are some of the common exercises you find on internet and are recommended by mostly all of PTs. But when you are done with your sessions, there is no one to tell you at home about not exaggerating your neck while doing chin tucks. But the book did with amazing visuals.
PT (4.5 yelp reviews) did lot of trial and error solutions focusing on strengthening and mobility exercises. Great, if something worked, otherwise continue trying different solutions.
I also had to meet $1500 deductible for my insurance to cover these PT sessions but I could only afford 2 sessions a week. This point was not an obstacle but I wanted results from PT after 3-4 sessions to justify the cost which didn't happen to be the case for me.