I think it is also important to differentiate how commercial labs and amateurs works. On one side big tanks with a minimum of 4 liters and up to 50 liters of developer where a humble piece of film pass though it avoiding aireation as much as possible; on the other side an amateur on the bathroom processing film in a small tank with 0,5 to 1 liter doing manual inversions. I don't think both can apply the same replenishment practices and even in some cases it will be not possible for the amateur.
In a Jobo-like rotary processing aireation meets also a very low volume of working solution. I can process in my Jobo CPP2 a 35 mm roll with just 125 ml, or process a 8x10'' paper sheet with 100 ml. The price to pay is that most working solutions are one-shot, still expensive from a large commercial lab point of view but very covenient for some amateurs like me with ocassional use of the darkroom.
In a Jobo-like rotary processing aireation meets also a very low volume of working solution. I can process in my Jobo CPP2 a 35 mm roll with just 125 ml, or process a 8x10'' paper sheet with 100 ml. The price to pay is that most working solutions are one-shot, still expensive from a large commercial lab point of view but very covenient for some amateurs like me with ocassional use of the darkroom.
If you want to pose as experts, please pay attention to detail and be comprehensive.

