Woops, I thought u were talking about the fact that the afd itself moved forward and back, changing the height of the afd. The actual thing that slides is called an afd (anti friction device) it is designed to prevemt ur boot sole from sticking upon release, therefore ideally preventing twisting fall injuries, torn acl/mcl
Oceanography?!?! Is that like pornography in the ocean?
What if skiing had some horrible side effect; like it gave u mad pimply balls.
And what if snowboarding was the only cure?