You didn't explain how precipitated anything can affect the pH of what is in solution. If pH is the principal concern, should we use a pH meter to decide when we have reached Rodinal, or will a development test suffice? pH meters are less reliable in the hands of amateurs than teaspoon measurements. What are the prime characteristics of Rodinal that would be affected by variation in pH? Most users of it are looking for a certain grain-gradation-sharpness character that they consider unique to Rodinal. If pH is a critical variable in determining those characteristics, then pH of the working solution should be critical as well. Is it?
A saturated solution of potassium paraminophenolate should have a certain pH. The concentration of sulfite may have some effect on how concentrated a saturated solution can be, but I cannot see how precipitated p-aminophenol can affect pH. It is not ionized, is it?
If using p-aminophenol or the hydrochloride makes a difference, why did not the recipe discovered during WWII use the hydrochloride? The amount of hydroxide is in fact almost but not quite enough to convert all the specified amount of aminophenol to the phenolate.
If someone can show by experiment, and not by fanciful imaginings of what goes on in the mixing tank, that the order of mixing makes a noticeable difference I would appreciate it. You can refuse to listen to anyone who does not have a degree in chemistry. I can refuse to listen to anyone who does not have a degree in common sense, but I do not. In all my years at NASA, I engaged in many different research projects requiring many different fields of expertise. What I needed to know, I crammed into my brain both during working hours and at home. I found that having a degree in anything was a license to learn aout everything.
Did I tell you I grew up in Missouri? Show me.