I was thinking about the challenge of getting nut slots adjusted perfectly and then thought about zero frets which would seem to eliminate that problem. My idea is this: Cut slots on the back side of the nut- these would keep the strings from moving around. Then leave the front portion of the nut smooth. This way there is no nut material coming up the side of the strings. I'm probably not the first to think of this...What are the pro's & con's?