You could be on to something. Has the OP confirmed that it is indeed walnut? If it is swamp ash, it would bleach out much lighter and could be stained almost any color. Not sure about the black and sanding though.....Id have to see it.
The black just enhances the grain, here's a tele i built for my wife. After sanding off the black, i stained the maple dark blue and removed most of that. She wanted that worn jeans look.
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