Thanks all for your replies, another forumite kindly sent me a spreadsheet of a sea vixen pilot's logbook from 65 onwards for which I am very grateful.
I can understand that one would be introduced to actual deck landing gradually rather than thrown in with a night landing in a Biscay storm straight away ;-)
But that 25% attrition rate is beyond sobering. Presumably this was all stages of training up to being "carrier qualified" but were the majority of the losses down to carrier operations? Or some quirk of the Sea Vixen? Hats off to those young men, anyway.
Another trivia question - but what was the typical airgroup for Victorious, Hermes and Eagle when operating the Sea Vixen? I have found some quite wildly differing numbers on the internet.