I believe Django damaged his fingers in a fire.
Richie Havens was playing in an open tuning. Don’t know which one, offhand. As the open strings in that tuning produced a major triad, he was able to play major triads up and down the neck by barreing. . Playing minor triads is not nearly as easy, although completely do-able with a bit of practice. I don’t know whether Havens never learned or whether it was a musical preference but at times he would cover songs that included minor triads (as originally written) and play them with all major triads. BTW, his extended Woodstock performance of "Freedom" was made up on the spot, because the next scheduled act was not ready to go on and the festival organizers asked him to play more after his set was finished. Turned out to be one of the highlights!
Ry Cooder has used open tunings a lot and not just for slide. He’s often played rhythm parts in open D. He also occasionally used a 6 string bass to play rhythm parts! Open tunings can be a lot of fun. BTW, Dylan wrote/played most if not all the songs on Blood On the Tracks in open D.
I will reconstitute the list I sent you via PM here, once I get back from walking the dog.
