Mike, you haven't closed the logic loop of effect and cause.

But the bottom line is the assumption by you, Jek, Tenson et al that ATC do not know what they are doing. Whereas it is much more likely that they have good reasons for arranging their speakers as they do and not (for example) making Proac clones.

FWIW we don't even know the arrangement of the ATC crossover.

Paul