You class ASAP.

Who the hell told you not to class him?

just as richard said, the late classing is for pilots only( if you to overrvetting becuase when you class your pilots the grew less) and some AA guners but most of sailors you should class them ASAP

Correct....Class as soon as possible.

The seaman ability numbers are a Percentage not a true ability. The different abilities of all sailors are boosted by a function of this percentage in each ability catagory of the seaman. Present theory is that a 15 in, say repair, boosts all sailors repair ability by 1.5%. Other ability catagories are boosted depending on the seamans ability in that catagory.

Therefore, Class as soon as possible to get maximum growth in all abilities. Remember that Vets and Experts in a seaman also increase the seamans "boost" ability.