Hey Jeff,
What appears to be a "crude" tuner is actually part of a folded expansion chamber that likely underwent thousands of hours of dyno time to develop. Remember that expansion chambers typically make power in a narrow powerband best suited to applications with VSD's or multi-speed transmissions. Outboard two-strokes require a much broader powerband that necessitates a totally different tuning approach. Never underestimate factory design features. Each and every single part was developed for a purpose. End users don't have a clue as to the time and $$$ invested to make those engines work.
Tim