Hi,
Not all lenses are created equal. Some lenses are stellar and some less so.
In the 90-es Photodo tested several hundred lenses using Hasselblads MTF test rig (and personnel). Photodo also had a grading system, going from 0 to 5.0, with 5.0 being theoretical maximum. The Hasselblad lenses tested came in at 3.1, 3.9, 3.7, 3.6, 2.7, 3.6,3.7 and 3.1.
Mamiya 7 lenses came in at 3.7, 3.8, 3.9, 4.3, 3.8, 3.5 and 4.1, so they were better on average the Hasselblad.
Some Canon lenses came in at 3.9, 4, 3.9, 4.4, 4.4, 4.6, 4.1, 4.2, 3.9, 4.5, 3.9 and 4.8, with the last being the 200/1.8L USM.
A lens that is know to be stellar is the Zeiss 21/2.8 but the Zeiss 25/2.8 was not a very sharp lens.
The Leica lenses for the Leica S2 are said to be the best lenses there are, but when "Diglloyd" tested them on the S2 versus a Nikon D800 with a Zeiss Macro Planar 100/2 the Nikon/Zeiss came out on top.
On the other hand Schneider and Rodenstock (now called Linos) build specially designed lenses for MFDBs with a small image circle but very high resolution. At least the MTF curves in the brochures look impressive, specially if you note that the lines go up to 60 lp/mm, instead the normal maximum of 30 or 40 lp/mm.
What I would say that you need to look at individual lenses and individual samples. Then comes the other issue of bringing that MTF to sensor. Many cameras that don't have live view are not very easy to focus exactly.
Alpa builds a couple of technical cameras with very exact helical focusing and select Schneider and Rodenstock lenses.
In general, a lens that gets diffraction limited at a larger aperture is always better than one that needs to be stopped down more. So, if a lens needs to be stopped down to f/11 for optimum sharpness that lens will be much less sharp than a lens that needs to be stopped down to f/5.6. Why? Because the optimum aperture is where the lens is limited by diffraction.
And yeah, if you stop down a lot, all decent lenses will be similar as MTF and resolution will be limited by diffraction!
Best regards
Erik
Many know by fact that MF glass renders less detail by square centimeter than 35mm glass. Large format glass lose even more detail. I doubt Zeiss is just recycling MF lenses. Just like that, they would not do any better than standard 35mm lenses, though they could be better in all other departments like color rendering, distortion and CA control. But the main goal I believe is sharpness and detail to match dense sensors without sacrificing the other. If they are indeed MF lenses, they better be HEAVILY modified for 24X36.
Eduardo