Hi Max and Mike
Yes, this was the good explanation. A curve is as measurement?longer but straight?the boat has the good length. The rest?is correct, the transom thickness. By the way, I can imagine the insecurity of a new builder. I am one of these persons who make the work (for some boats to get the correct length) of the curvature. By the way, intolerances of patches of plywood are more inaccurate. So if the boat is a fraction to short or long, so what? you will feel no difference.
Bernd
Bernd Kohler