@ChrisB - out of curiosity, I tried to find out whether anybody asserts trademark rights for the logo and have not been successful. The DSA does not on either website or the DS Quarterly, the current builder does not appear to make such assertions either. Make of that what you want.
I don't speak for the DSA, but I can't imagine why your particular personal use should interest anyone. In fact, if you were to ask them for formal permission, that might actually create a problem....
One design classes are an interesting type of product, because the class association is in charge of confirming the "class-legal" status. That makes a difference in terms of who might abuse the rights in a mark, say, for a competing product. If a competitors product is not class-legal, then it's worth a lot less, no matter what logo is on the sails. This would be the total opposite of the designer handbags, where the status is entirely conferred by the logo (and that's why some bags are indeed covered with it
)