I wonder if it's a matter of the math not matching the measurements, unrecognized variables, or errors of another sort?
For your consideration: (sorry, but most of the links no longer seem to work.)
https://www.audioholics.com/gadget-reviews/speaker-cable-reviews-faceoff-2/speaker-cable-reviews-fac...
The authors suggest that the supplied RC networks values for the MI 2's could be improved upon, perhaps someone might be able to confirm or refute this. Furthermore, I would be most appreciative(!) if instructions for construction of the ideal zobels for the MI 3's could be provided.