The layer of disturbed air near the surface of the water greatly reduces the impact of a mid pole snuffer, it is essentially tucked away in the already effected flow around the hulls.
When the Tornado started with snuffers as compared to tramp bags there was a lot of straight line testing done and the result was that the mid pole snuffers had no impact compared to the tramp bag systems, and some even tried a snuffer system in the tramp a lot like the one wayne has but even smaller vertical profile and these were prone to wave impact.
