And someone without it would even understand the command?
Really... And yet most just happens to do things right even without being told anything. Out of 19 crew i saw, 2 or 3 looked like possible noobs. The rest certainly had experience.
Oh, and ~20 crew? Thats a big number for anything not a warship of that size. 6-14 would be more realistic(for the tonnage, as noone had modern racingboats at the time).
Fair enough. My preference would be to give an average sailor Profession Sailor 3-6 with possibly 1-4 in one, at most 2 of the other skills. Ie, i dont consider the secondary skills a must have. But several of them might be an almost must have for a ship overall.
Things break alot. Whats boats made of? Mostly wood. Someone with profession shipbuilder is better, but being able to work wood reliably isnt the same as knowing how a ship is made overall, and those good with shipbuilding tend to be busy doing that somewhere on land.
Noone said anything about "being a carpenter is like being a sailor", but a sailor who knows carpentry might be a very useful person.