The parent comment was comparing DJ equipment to a record player (to this patent), which I feel is a poor example because modern DJ equipment almost always has different equipment too rather even if you could technically do it with a fader and some record players (as in at a gig, I'm aware people still mix on vinyl - pretentious as it can be).

The patented guitar thing is literally played the same way but in a different place, which I think should really be considered prior art unless the fashion aspect is considered rather than purely functionality.