I'm not sure you've hit a nerve, just saying the square top is not in or part of the class rules is all. Don't get me wrong, you can do what you like, but I'm saying your sail would not measure as a Mosquito Class Sail.

But in saying that, let me say this...You could just as well build a Taipan, put a square top on that is already class legal and built pretty much the same way.

I would never discourage anyone from building a boat, its a great journey, good luck.