I haven't heard of that one, but I have heard of simpler tricks like re-tuning one string so the third of certain barre chords comes out right. There's always

I haven't heard of that one, but I have heard of simpler tricks like re-tuning one string so the third of certain barre chords comes out right. There's always a bit of a trade-off; some intervals get better and others get worse so in effect you're optimizing the instrument for a particular playing style or key or song. If you're willing to modify the guitar to put frets in different places, it allows for a lot of options you wouldn't have otherwise. (This is especially true if you're willing to use partial frets.) Kite tuning is the best scheme I've encountered for having closer-to-just intervals than 12-TET and yet you can play in any key. If you want perfect intervals, plain just intonation is better but then you're locked into a particular key and scale. The design space of guitar fingerboards is surprisingly huge and open-ended when you stray even a little from the twelfth root of two as the fundamental unit of musical interval width.