So many awesome parts about this article, it's hard to choose only one, but I'm going with this:
"The device was now packaged with a large disclaimer warning it would only repel sharks when the surfer was still in the water waiting for a wave.
'The surf product only can be guaranteed to work when it's stationary, not when it's surfing in the wave or paddling,' Mr Hartley said."
Ah, OK, to be effective, I have to play dead. Got it.