When you’re as dialed in on a surfboard as Mick Fanning is, small things make a big difference. Now, I’m a pretty firm believer that, for the Average Joe, fins don’t matter all that much.

Robyn Jackson, 30, from Leeds, was surfing in Cornwall when a wave threw her off "wedging my surfboard fin through my wetsuit and deep in my leg". The same wave sent her board smacking into her ...