Biggest gimmick in bowhunting- whisker biscuit, and anything with the name Limb Saver on it.
I thought it was pretty much universal that archers recognized that LimbSavers reduced vibration. To me, it's so easy to detect the difference between a bow with no vibration dampener and one with a LimbSaver on it. I'm surprised that anyone thinks they're a gimmick. They may be overpriced and over-hyped, but they're hardly a gimmick.
I have tendonitis in my bow arm's elbow and shoulder. When I use to shoot a bare bow without limbsavers (several years ago), I was in quite a bit of pain when shooting my typical 300-400 shots per week. After adding the LimbSavers, not only was the bow much quieter, with less vibration, but the pain from shooting was gone within two weeks. Gimmick? If so, I hope more gimmicks like that one make it to the market.