RE: what fin size for a 6.8m on a S type104
My experience with fin manufacturers has been at both extremes, so I think it is usefull to have some knowledge in addition to their advice.
I agree that there a too many variables in fin selection but a managable amount if you stick to just the area selection. I know my formula is simple, but how do you find it too vague for the purpose and parameters stated?
It seems to me that the formula and the publication of fin area achieves your stated objectives so we have the same desired objective. What is your exact concern with my method?