The point of a 3, or better yet a 2, string is to play minimally and have fun. As well as to jump around more on the neck. It's an interesting challenge. And did I mention fun?
It's also a bit of an in-joke, both because of extended range basses and guitars, but also because many people either don't use or joke about not needing the upper range of a bass.
It can be argued that our instrument originated as a 3 string, since that's how many the first orchestral uprights had.
The Bass V was absolutely not short scale. It was 34", exactly like a P or J.
It was a terrible idea. Nobody wanted them, which is why they only sold a few hundred and then cut the leftover bodies up to make Swinger guitars.
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