A few notions and questions here. I'm pretty new to the subject so please pardon me if I have mistaken something elementary.
1) 21:9 Ratio TV's are mostly out of Market today. Philips killed the production of 21:9 TV's this autumn. In USA Vizio is still selling. (?)
Meaning this device sold 2009-2012.
The best benefit of MFE can be get with 21:9, 2560 x 1080 screens, but the markets are dead for them, at least for the time being.
2) In Philip's Cinemascope 21:9 TV's, the maximum input signal is 1920 x 1080. So, even if the Blu Ray player gives 2560 x 1080 signal, the TV set doesn't compute it. - Or at least not in the proper form.
Have I understood it right? - Have you tested at the Folded Space how the Philips Cinemascope reacts if you try to input 2560 * 1080 signal?
3) Wouldn't it be best for the picture quality if the soon becoming 4K format adopted a native 21:9 ratio? (That would be 5120 x 2160.)
I understand that for the Folded Space this solution wouldn't be the best, since then the MFE wouldn't be needed for the 4K.
4) As I see it, MFE is very much welcomed, but doesn't yet solve the whole problem. To me it's a problematic that 21:9 aspect ratio sets that have 2560/1920 = 33% more pixels in their sets have to settle only for 810/1080 = 75% of pixels when comparing to 16:9 viewing standard Full-HD TV program.
If I have understood right, MFE does solve the problem for the missing 25% resolution for 21:9 format, which is more than fine and really an unecpected joy that the Blu Ray format could be thus upgraded so eloquently!
When it comes to 4K however, why not aim to actually give the 21:9 viewer more pixels than for the 16:9 viewer? For the point of view of a manufacturer (and especially their marketing!), this would make much more sense than just getting even with the standard 16:9 sets.
If all was lossless the current 21:9 TV could perform (2560 x 1080) / (1920 x 810) = 1.78 times more pixels in cinemascope movies than the current Full-HD with letterboxes. The same relation will happen with 4K. That is if Foldes Space tech isn't used.
5) Stupid question on MFE: Does it only enhance the vertical resolution, leaving the horizontal resolution intact? Or does it spread the exrta resolution evenly for horizontal and vertical resolution, since the data for MFE Blu Ray disc is extracted from a higher resolution master tape?
(If it's more data on 1080/810 = 1.3333, then both horizontal and vertical resolution could be enhanced by SQRT 1.3333 = 1.1547 that is by 15%.)
6) Is the bottom line of MFE that less upscaling is needed? (And that the upscaling can get more exact.) Since the MFE-coded data packet from blu ray disc can deliver the information equivalent of 1920 x 1080 (in 21:9 aspect ratio) there is less upscaling to be done than from the 1920 x 810 information packet. But since the MFE-coced packet only contains the information equivalent of 1920 x 1080 of data (in 21:9 aspect ratio) there's still upscaling needed to the all-full 2560 x 1080.
Did I get this right?