you could remove the nut ... and mod another nut.. !? then you'll always have the original nut when it's time to go back to more normal tuning .. !? or make a nut for the BEAD tuning versus drop D or C . ?
If there was something to it, there would be a double sided but, that you can de-attach yourself and just turn on it, and on the other side of the nut, the slots are filed for thicker gauge. Wouldn't turn out that complicated. But a zero fret allows for any gauge. Any time.
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