I think the difference is that with a copy of the CM in hand, the builder can say "yes, I built this to the exact specs in the manual". If the CM is taken away from them they'll be going on memory, if they say "yes, I built this to the exact specs in the manual" someone could respond "how can you be sure, did you read the manual while building it?" of course the answer would be "we remember how to" which wouldn't stand up to scrutiny...
Basically possession of the CM is a way to guarantee that all the boats built are correct as they can refer back to the original instructions. Without the CM the guarantee is that the builder has a perfect memory.
Basically possession of the CM is a way to guarantee that all the boats built are correct as they can refer back to the original instructions. Without the CM the guarantee is that the builder has a perfect memory.