Dignan did his work with early C-41 films. He did it correctly, using proper sensitometric and color control tools, and got a developer that worked decently and got many excellent reviews at the time. Although that developer tended to have the advantages of a black and white divided developer, it was still quite fussy about composition, times, and temperature. The reference the OP gave showed pictures made with a modified formula which really looked pretty bad, with magenta highlights (not shadows). Scanned postings are always difficult to judge, in any case. The deviations from the prescribed recipe may be part of the reason they look so bad. the formulas always were fussy. We need to note here that color films have changed a lot since Dignan did his work. The changes were calibrated for standard C-41 processing, not for Dignan's soup. The two bath solution may not work as well with these modern films as it did with the early films he used.

Dignan NCF-41 Divided Color Negative Developer
For C-41 films

Prebath
Water 800 ml
Sodium bisulfite 1 g
CD-4 11 g
Sodium sulfite (anh) 9 g
Water to make 1 l
pH at 75F = 6.5

Activator
Water 350 ml
Potassium carbonate 53 g
Potassium bromide 500 mg
Benzotriazole 2 mg
Water to make 1 l
pH at 75F = 11.8

Treat film in prebath at 75F for 3 minutes. Drain for 15 seconds. Treat in activator at 75F for 6 minutes in tank, with continuous agitation for the first 15 seconds and one inversion every 15 seconds thereafter. Treat in activator at 75F for 5-1/2 minutes in drum processor. Provide a 15 seconds drain after the activator and before the stop bath. An 87 g /l sodium bisulfite stop bath at pH 4.8 was recommended.
Ref: Dignan Photographic Newsletter, September 1979