Thiel 2.3 vs 2.4 the real difference

Art, I agree with what you said, but in my case I was intimately familiar with my 2.3s. But not with the dealer's (excellent) room and equipment. As the 2.4 is so similar, it was the differences to the well-known 2.3 that stood out pretty clearly. No doubt if I replaced the 2.3s with 2.4s in my own room & equipment, I'd hear a lot more of the subtleties between the two. But that wasn't an option at the time and I just don't think the differences are much more significant than what I heard in a different space.

Side by side is the only reliable way to tell minor differences. Our ability to remember subtle changes in sound is poor to say the least. Memory does funny things and is more affected by other stimuli than most would admit. Tests have shown people tend to find differences when no component had actually been switched. As for the Orions, I am still putting them together. The cabinetmaker left out the screws for the drivers and some pilot holes were misplaced and others missing altogether. Part and parcel with DIY stuff I guess.

Did anyone took the mid/tweeter driver out of the CS2.4? I am just curious if Thiel really make the drivers themselves as it is not viable to manufacture a relative small number themselves or, what I suspect, Thiel is installing a(n) (OEM) version of a known brand like SEAS or Dynaudio in the CS2.4

The rationale behind it is to get a cheap(er) CS2.3 and mount CS2.4 mid/tweeters.
There is a good reason that Thiel wouldnt sell the CS2.4 coaxial drivers by themselves or put them in a CS2.3

Thiel used to use outsourced drivers that were modified to Thiels specs. They've been using their own drivers for some time now. The most recent ones, such as those used on the 3.7's are clearly very different than those used by others.

That 2.4 mid/high driver is very different from others manufactured by the company. There is no electronic crossover but instead a physical transfer is designed between the two drivers (common coil used) based on the polymer that couples/uncouples these two portions of the driver depending on the frequency.

This is a superb forward thinking design with excellent coherence and minimal phase shift in the transfer region.