I haven't read this whole thread yet, but perhaps this little story is somehow applicable:
An experiment was apparently done many years ago, where people were given glasses that would turn the image upside down. After about 3-4 days or so, the brain of person experiencing life in an upside down mode would shift the vision so that it was right side up again. When they took the glasses off after this happened, the image would become upside down without the glasses--which would last another 3-4 days. I don't know whether this fits in, but it seems like a pretty good example of how the brain can make adjustments if prodded in certain ways. Which could of course be beneficial for some people with tinnitus.