He pretty much dropped out of the public eye so long ago--and did it absolutely. In the late 70s, we tried a variety of good personal connections to persuade him to perform at MIT and the answer was a resounding no. Add to that a relatively small body of songs and there&#x27;s just not a whole lot more to say past a certain point.<p>Edit: That said, there have been a couple of in-depth articles relatively recently. I suspect the issue is that they needed a lot of research that went beyond easy-to-find sources.