I wish I had written the numbers down, but when I first went tubeless, I planned on auditioning three tires, (1) Schwalbe Pro One 23mm, (2) Maxxis Padrone 23mm and (3) Specialized S-Works Turbo 24mm, and i measured each tire across it's carcass (uninflated).
I'm *pretty sure* that the Pro One measured widest, even more than the Specialized with a wider "stated width." I ended up really liking the Pro Ones and with the rolling resistance and reviews out there, never actually mounted the other two tires. I would guess that they would measure out narrower when mounted, since they were physically narrower bead to bead when laid flat, but maybe there is some magic shape property to one or both of them that would challenge my assumption. Of course, if they did measure wider than expected when mounted, this would seem to mean that they were "flatter" tires and that would seem to be sub-optimal from an aero perspective.
I don't think we can ask much more from Enve than for them to say a given rim shape is designed for use with a tire with a "stated" width of __mm, but I do think there is variation within tires of the same stated width and so the recommendation is really a good starting point but not necessarily the optimal end point.
Amateur recreational hobbyist cyclist
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