Sporting Sails For Downhill Longboarding

The idea was simple - use a windsurfing rig ( mast, boom, sail ) to have more fun with my longboard. So, I was looking on Amazon to buy a sail, when I came across this :

Sporting Sail elevates the sporting experience from a rushed downward dash to a weightless, flight-like glide that allows one to explore the use of wind and air to control speed and stability.

Nick and Billy Smith, California-born brothers, got the idea for the sail from their grandfather, who invented "Ski-Klipper", to help downhill skiers catch air and slow down on steep descents.

The brothers reinvented the idea,and found their own niche when they realized that "there are 18.5 million skateboarders worldwide, and not a single efficient braking system on the market".

According to their web site " SPORTING-SAIL allows to carve bigger and longer hills on smaller more playful set-ups, and in the process, draw new lines on the land."

While this might look like a good idea, using slide gloves might still be the most effective way to stop/slow down when longboarding. And I'm not sure why would somebody use Sporting Sail for downhill skiing/snowboarding ( not to mention surfing ).