Carry on carbonate:
(1) MDS-1 is an approximate copy of the latest Diafine substitute [see link below] with the phenidone replaced by 10x its weight of metol, to avoid streaking with these [near monodisperse?] aerial films. I have some examples of Adox HR-50, Rollei Retro 80s and Rollei Retro 400s on Flickr including this where I got E=400 by a foul, the camera took an average reading from the dark background:
https://www.flickr.com/photos/98816417@N08/51299921335/in/dateposted-public/
The best EI for these films in MDS-1 is still to be found.
(2) A better explanation for development in bath B of 2-bath developers can be found than the oft repeated statement that development in the highlights [black on the negative] stops due to developer exhaustion. Since the part B of Emofin could be used 15x and that of Diafine many times, there would be some carry-over [20ml] from part A on each transfer to the tank and reels as well as the film on replacing part A by part B, making the part B a dilute developer.
Referring to dilute developers [actually the high acutance type], The Film Developing Cookbook 2020 p67 is paraphrased:
"...as the developer is very dilute, it exhausts quickly in the highlight areas where there is a lot of silver to be developed......At the same time the developer does not exhaust quickly in the shadow areas so these are free to develop much more than would be possible with an ordinary developer......can produce a speed increase of 50 to 100 percent with conventional slow to medium speed films....the effect is usually less with tabular grain films. "
(3) MDS-1 is not quite the same as a copy of the carbonate version of Diafine substitute, it contains 30g/L carbonate and 35g/L sulfite, pH~ 11.5 and probably gives a more grainy result.
https://www.flickr.com/groups/diafine/discuss/72157699627118502/, however both are based on a carbonate sulfite mix.
I found the B bath of MDS-1 [carbonate sulfite] gives notably higher density than a B bath of metaborate, possibly due to the carbonate absorbed in the emulsion resulting in faster development and more density before it diffuses out.
(4) Lachlan Young sent some literature [thanks] indicating that at a metol concentration of 0.2 g/L, the addition of HQ [as in MDS-1] reduces edge effects by about 40% so that a higher acutance developer could be made by replacing the HQ in part A of MDS-1 by metol, which would then be the only developing agent. However, I will not change the formula halfway through the experiment.