a non solvency effect may give that impression, try fx-1 and reflect about impression of sharpness. And yes sulfite must be present for superadditivity just try it in a paper developer.
Superadditivity is a little off in the weeds wrt adjacency effects, of course, but it's obviously quite relevant to developing times. Here's the passage I found, from Bjelkhagen, _Silver-halide recording materials: for holography and their processing_ (it's a monograph published by Springer in 1995):
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Comparing the PQ and the phenidone-ascorbic acid developers (PA), the following must be observed. As already mentioned, van Veelen and Willems [4.44] have studied the influence of sulfite on the superadditivity effect of these developers. If there is no sulfite in a PQ developer the superadditive effect will be drastically reduced. A PA developer, however, will be almost independent of the sulfite content. The reason for the sulfite dependance[sic] in a PQ developer is that the regeneration of phenidone by hydroquinone can only occur if sulfite is present. In a PA developer, regeneration occurs even without sulfite.
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Bjelkhagen is looking at holography rather than conventional photography, but reduction of activated silver is the same in both worlds---I can't think of any reason for this analysis not to apply, though maybe some of the people with real photochemistry chops can give a more informed opinion.
The relevance to your project is that switching from ascorbic acid to hydroquinone might force you to add some sulfite if you want to retain similar levels of developer activity, because otherwise you'll lose the superadditivity that phenidone and ascorbic acid display even in the absence of sulfite.
That said, I'm just taking Bjelkhagen at face value---in principle it should be easy enough to do some experiments with "P-TEA", "C-TEA", and PC-TEA and determine whether there's a noticeable level of superadditivity at play. (But per the Film Developing Cookbook and a lot of conventional wisdom, neither P nor C works well as a sole developing agent...)
On top of everything else, TEA itself is a mild silver solvent, and for all I know it might affect superadditivity as well. Bottom line is that you probably could have mixed up a batch of PQ-TEA and done some experiments to find a set of starting times in the amount of time spent on this thread...and I think that's what you'll have to do anyway.
My goal was to formulate a looong lasting high acutance (more or less like fx-2) developer with a known time table of developing times, this convenience comes from the fact that i want to introduce this developer in a school and without a times guideline its a mess
Maybe I'm missing something, but for school use, why do you need to strive for extreme adjacency effects? (And are you really likely to get something similar to FX-2 without using glycin?)
-NT