I always forget I’ve got a third finger I could use until I get to Fahey (or someone like him). I just wrapped up a Peter Lang song that had similar requirements.
But, that’s what I like about Jorma Kaukonen. The third finger is almost like a safety net for me 
I taught guitar to a couple of kids and had no idea they were both lefties for years. They somehow managed to use a right handed guitar strung like a right handed guitar.
