Never used a leash ever, and never thought is was a good idea, but I've seen a in a number kite mags a lot kiters using them in surf (surf style of leash).
Is it ok to use leashes in surf vs. TT with a recoil type of leash?
I'm heading to Barbados this March, and saw a comment that a leash might be a good idea because of the rocky shore line. I guess this makes sense, but still concerned about getting smashed in the head with the board.
The simple answer is that it depends on the conditions. If you watch some of the ben wilson guys that charge huge waves in sketchy spots, they use a board leash, and no kite leash. So if they get into a dangerous situation, they unhook the kite and try to paddle in safely on the board.
If you're just riding in typical conditions a leash just gets in the way, it's a lot easier to recover a surfboard than a twintip because it almost always ends up downwind of you. Worst case scenario it ends up on the beach.
If there is no beach, IE rocky sketchy launch, that's when you use a leash.
- there are rocks to lose your board on - the waves force you to ditch the kite and use the board as a safety device - the waves and current can force a swimming person to land on a sketchy coast
And wearing a helmet in waves is always a good idea: a surfboard is prone to be smacked in the head more easily than a twintip by serious waves (and I am a real world witness: it even crashed the helmet!), but a helmet is no panacea, I also got smacked on the nose and cut my hands and feet on the fins
win and loose with whatever you do I would say. I think it is important how to protect your head when you fall having a board leash.
When I am getting washed by a wave (small) I put up my right arm behind me head to protect it from my board hitting me, and I am riding without a leash...but the board gets washed from the wave too and can get smacked on your head. Don't know about big waves, might even hit your forehead.
Good answers about the cases when a leash could be good
In all other scenarios (in fact maybe most of the conditions and wavespots kitesurfers ride in), I would not use it.
The catapult effect is one thing, but everybody are aware of this and the risk nowadays - so no news here.
But one thing that can be really annoying - or dangerous - is when you tumble in a wave (also really small waves), and the leash (thus also sometimes your board/fins) gets coiled around or inside your bar and lines
Not good - and an effect/risk many havent thought of, because it almost never happens on a TT - but in waves it is much more likely to happen, as we have discovered/seen several times
On a TT even in big waves, I didn't use a leash: I have straps on my TT, so is very difficult to loose it. Moreover a leashed TT, due to the lack of volume, tends to dive when pulled...and here it becomes dangerous. On the surfboard I use to ride strapless and in small waves, or very near to the shore I don't use the leash, so if I loose it (and it happens) i can rescue it easily. When I ride the same strapless surfboard on bigger waves and/or the peak is far from the shore, or Iride a dangerous spot, I use a leash: you never loose the board, you can rescue it quicker and escape from an upcoming set, the surfboard has a high volume so even when pulled it doesn't dive and slingshot on your head