dont have time to read all this, but i know that there are created averages and percentages that calculates how often songs are played by each musician for each year, and they get paid based on those calculations. so no, if you only play jackson browne songs, jackson browne does not get all your money. but, jackson browne gets a percentage of all the pay that ALL recorded musicians make from the year, including thousands of performances where his music was not played at all.
im stoned and dont know if that makes any sense at all. but i know im right.