I know it is not the answer to you question, but maybe a solution for a problem u have, like me: The Boat Total/Start Weight.
If you don't mind adding mods you could install this mod: CustomShip(add Ship MaxExperience)
It's weird described, but what it does is it changes the start weight of the boats, not the per level unfortenately.
What it does in the .ini after installing the mod, you can set the added start boat weight. For example 10000 extra weight.