Originally Posted by Cookee
A golf ball spins and this won't.
Water will follow the hull and flow into the dimples as there won't be a sharp edge to separate the flow from the hull.
Making it would also be a nightmare.
I'm sure someone would of tried this before and if it worked we would see this everywhere.
Cookee - that seems a somewhat blinkered view to possible innovation. Everyone told James Dyson that if there was a better way to make a vacuum cleaner Hoover and Electrolux would have found it. Given, as you say, the complexities of making loads of dimples in a hull, that actually fluid dynamics are not as well understood as many people think especially when air, water and solids all interact and that a lot of boat building and design has been about gut feel and trial and error rather than computational models - even if someone thought it might work, that doesn't mean they would have turned it into reality with the right size dimples distributed in the right pattern etc.
Although the idea has been known about for years in golf balls, its only relatively recently that people have started to apply the concept to aircraft: How golf ball
Of course there may be downsides to it too, and any advantage (if there is any) may not justify the cost increase from complexity of production for either average or high performance users, especially compared to other approaches like steps / scallops etc.