I read the 6moons article before my post; in fact, the article prompted it.
The only "electrical" cross-over is from woofer to midrange at 150 HZ. The crossover from the midrange "balls" to the tweeter is purely "mechanical", i.e. the natural roll-off of the drivers.
As for the change in capacitors, sure it can affect the sound somewhat, but that change in sound at a 6 db per octave slope from the crossover point at 150HZ, to be significantly audible, would lie in the lower midrange (150-600 HZ, at which point it would be down 12db) where that type of coloration is difficult to discern. (Note that the same 6moons reviewer in his original review of the Ref 3 did not note any "grayish" (whatever that means) coloration in the midrange (nor did anyone else)). Note also that the recent 6moons article seems to attribute the bulk of the change in sound the reviewer claims to hear to the new magnets. "Most noticeable is the new mechanical handover between the balls and CDT II" (i.e., the tweeter), he claims. The capacitor effects an electrical cross-over between the woofer and the "balls."
But then I'd have to believe that after Gallo spent years working on the development of the Ref 3 (as the Gallo literature claims), he suddenly discovered there was a problem with the capacitor and that it just coincidentally occured to him at the same time as the introduction of the new Ref AV?
As for things that can affect the sound of the speakers, the main factor is the listening room itself and its furnishings. Then there's the associated equipment and cables and even atmospheric pressure, not to mention the shape and accuity of one's ears. All in all, don't get too hung up by what a reviewer or manufacturer claims and listen with your own ears.