The problem is that there has not been any large sample, long term studies on this. But to my mind, it just makes sense. Anything you practice consistently, you get better at. Why would listening be any different?
I had posted in another thread on the same topic that my own experience leads me to believe it is effective for those who practice it consistently. I just talked with a patient here in our office who I met for the first time this week who swears by it. She used RMQ, (Read My Quips), and the Hear Coach App games faithfully 4 to 5 times per week, 15 to 20 minutes a session, for a year. She is also an avid reader, so she started reading out loud to herself. This started in 2015, and when she was in for her first annual re-test in 2016, they found her speech discrim in quiet had improved by 16%.
I know it’s only one person, and not everyone will improve that much, but it only makes sense to recommend such activities to our patients if there’s even a shred of evidence that it works.