I think it's a fair point about the acoustic center, in part because I asked just that after I saw this wild tweeter demo'ed in Munich last year. I am no professional loudspeaker builder but seeing, for example, Wilson Audio going to all those lengths to time-align their drivers, it certainly seemed obvious that it should be considered unless you want it to bite you in the ass. (No) pun intended
Unless severe, isn’t phase alignment much more important than time alignment?
If it’s was such a huge deal, most tweeters would be placed behind the woofers in an offset cabinet, and one of my speakers do just that:
And I wouldn’t bring up Wilson to illustrate the importance of time alignment.
Back to this tweeter, I did find it odd that this expensive, supposedly amazing driver doesn't have full measurements, Christensen's webste has this though:
but then I saw that email saying they are taking it slow, so I guess they don't want to be inundated with emails. But, while I hope it is amazing, when the only other products the company has are RCA interconnects at ~$650 for a 2m pair, and ~$900 for a quad set of damping feet, I would not expected it (though if I understand, this was designed by someone else, and Arya Labs picked up the design and developed it).