You build your own basses i assume? Have you played a Wal before? They've been building basses for years now and I don't see any reason for them to change anything. The 'blotch' doesn't bother me and actually adds to the charm and adds a nice contrast imo and contour is actually quite comfortable....per your wondering questions-why add unnecessary thickness to the bass.... also they can't use a thin core since they need space for the electronics.
Guess if it bothered anyone really, one can just get a solid body built instead of a sandwich type with a facing..
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