I doubt it'd do anything much to reduce felt vibration or provide any "benefit" for the engine itself as it's primary effect would be to reduce the noise you hear, mostly the clutch cover - which resonates like a drum head and amplifies the horrid sounds of poorly machined gears
The two most predominate sources of undue felt vibration are the stock "rag joint" rear sprocket adapter and the kit chain tensioner, it's true a single cylinder 2-stroke vibrates quite a bit, but it's not the worst cause with these kits BTW - replace those and it's a night & day difference