Jeez Macca, you are really being pedantic aren't you?
I fail to see the relevance of your questions pertaining to ANY "box rule" class. - You bring your boat and you race for, first across the line wins - That’s a formula. If you want to worry about the individual weights of individual boats you go and sail in a one design class (All their boats weigh the same – yeah right) or race on yardstick. Make your choice. If weight variation means so much to you why race at all, just weight the boats beforehand then award first place to the lightest boat without the necessity of getting your feet wet.
From your questions I can’t help but wonder why you don’t question the relative sail areas? What if one type of F16 cats all sail with their sails 1sqm less than the allowable maximum sail area? Would you be asking the same type of questions about the class for those reasons? IE “show me all the actual measurements taken of the sails as I don’t think it is fair that “those” cats were allowed to sail with a different sized sail plan”.
If as you intimate the actual weight of the cats relative to each other and to the minimum weight is SO critical to you then perhaps we should look at defining the “ideal” weight of the crew that sail on the boat and saying that – all crews SHALL only weigh between 75Kgs and 78Kgs, any crew who comes in over that weight shall be penalised by a sliding scale rating system and any crew under that weight shall have to carry “correctors” about their body. Your argument seems to be just that – an argument for the sake of argument – and pardon me for saying (please don’t take any of this personal) your arguments are beginning to appear a little irrelevant.