Nice lesson. I like the spice!
I like how you addressed feel. I have trouble feeling 1/8 note triplet strums that occur for just one beat (or half beat depending on how you count)… like at about 12 and 21 seconds (best example 1:14) in the following:
I know the above is not grass, but it is what came to mind. Thile and others do similar often. I can play it slow, but I can’t feel it at speed. Anyone have suggestions other than put on my big boy pants and work it up to speed? It’s like my brain doesn’t want to break the up/down pattern to fit 3 strums into the space for 2.