M-13...
I would agree completely with what you've said and would support this theory. In my mind, I have a clear and cataloged memory of the sound signature from the set that I demoed just over a year ago. This new set sounds exactly as you've described them. I also feel as you do that this is a deliberate move on the part of Audeze to improve the sound. And to most people, I think that they would agree that the sound has in fact improved as it seems to move closer towards lcd3 territory.
But, not to me. I am a self professed "dark signature" junkie. I prefer the darker sound of phones like the hd650 and Maddog. Much of the preference comes from being treble sensitive and fatiguing easily with brighter hp's, even with hp's that some might call neutral. Still, I refuse to give up that delicious extended audiophile bass that I still have firmly etched in my memory. If these "new" lcd's can't delivery the same bass, then I just can't live with them.