Basically you are saying that as long as the "max sail size" is pitched at the "right" level, you feel that the Uni rig is more efficient
No, I'm saying that I favour the sloop rig unless the class rules are written such that they actively favour the uni-rig by limiting the total sailarea to a prohibitively small size (= wrong size).
A basic Prindle 16 has a larger mainsail then an A-cat and even as a sloop it is considered underpowered ! I sailed my P16 singlehanded as a sloop rig all the time, because it was indeed faster that way ! As every rating system confirms.
Argueing to move the jib area into the mainsail is mute as then I can always add a jib to that rig and be faster again. Basically, for any given platform a maxed out sloop rig will always be faster than a maxed out uni-rig; because it will always have 25 % more sail area. We have covered this before.
But knowing this, the more interesing question is indeed why the designer of a set of class rules would choose to enforce LESS sail area then can be had with a sloop rig ? The only reason for it would be that he actively tries to prevent the sloop rig from being used in this new class.
There may be valid reasons to do so, but gaining higher performance is not one of them.
Now we can play words games till we are blue in face but the neither the race data nor reality will be different as a result.
Wouter