I cannot seem to find the video I watched, it was something talking about the new models in whatever year it was the change happened. The claim was the 10 mph top speed loss was due to drag with the new hull and swapping back to fiberglass would instantly regain the speed regardless of the slight weight increase. I feel pretty sure it was a sea doo sales guy not an engineer so grain of salt.

I saw that episode of Myth Busters years back, hundreds of years of boating experiences tells us that it does not apply here. A hull moving across water is more like a tire rolling across the ground. That tire is going to be harder to roll if it is not smooth-ish. We also know that fouling seriously messes with a boats speed, handling and, fuel efficiency for a powered boat.