Ability and fitness definitions needed.

Hmmm...I reckon 'Advanced' level does not refer to the Michel Bourez's, Felipe Toledo's or the Sally Fitzgibbon's, they are the 'Professional' level.
'Advance' level could mean non-professional surfers abilities, who can perform most of the manoeuvres that are performed by the Pro surfers but at a lower degree of execution?
'Intermediate' level could mean a mid-week/weekend surfer's abilities, who can perform a limited amount of manoeuvres that are performed by the Pro surfers but with a reasonable degree of execution?
'Beginner' level could mean the abilities of a person, who is relatively new to the sport of surfing, who has minimum hours of water time to begin with & is not necessarily doing manoeuvres performed by the Pro surfers of any kind...yet?

Maybe it would help if percentages were included ie "Advanced" equals, "In the top 15% of surfers at your local break". But then if your local break is Sunset and not Waikiki, then it all falls apart!