Can you explain what you mean by "This is... something that doesn't work well with text"? Text as opposed to what? If you were to "play" music by typing notes, then you would compare your typed note against the string of correct notes. Of course that sounds a bit silly, and probably not what you meant, so, please elaborate.
Sorry if that wasn't clear! I meant text as opposed to having verbal and physical coaching. My teacher would often demonstrate a technique by playing it on her piano, which was adjacent to mine. I even had a masterclass with one teacher who would grab my hand and guide it as she demonstrated what I needed to do.
An example of where text falls short: if I said "be sure to rainbow your wrist when jumping in that passage," it wouldn't make any sense unless someone had seen an explanation. I suppose I could try to explain "when moving higher, make an upwards arc, and loop around at the end, to prevent jerking your wrist around when going back and forth," but even then that's still way too ambigious, since there's also a certain way you need to pivot your wrist so you can hold onto the upper chord as long as possible. It's just much easier to demonstrate and see if the student did it correctly.
