A man surfs on a medium sized wave while holding a paddle that seems to steer him in the direction he wants to go.
An extreme kayaker steers the treacherous waters
A man surging is not assumed to be an extreme kayaker.  A medium sized wave does not imply treacherous waters.
Not every surfer is an extreme kayaker. Not all surfers can steer treacherous waters.
Not all men are an extreme kayaker.