I wouldn't ever claim to be the first to do anything, but I basically came up with that on my own over time. The first headstock I ever made from scratch had a headplate that was cut away to reveal the laminate at the end:
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Those first couple were cut freehand. After that, I switched to using a template with a narrower shape, and carving away a concave lip. This was the first carved lip:
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That shape was supposed to be my do-everything shape, and it went on a few instruments, but it was really cramped for big instruments and too big for small ones, so I replaced it with three new templates that I'm still using today. One is comically narrow, for tenor guitars. I like the dainty character of how slim it is:
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Then there's this version, which I use for 6 string guitars and 4 or 5 string basses, the template has tuner hole locations marked out for each:
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The third current template is that uke one pictured above.
And then for the occasional Fender style headstock, I move the cut-away lip to the side of the scroll:
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At any rate, I would encourage anyone and everyone to steal from me without feeling weird, because I certainly don't hesitate to steal ideas myself!