In the Darkroom Cookbook (pp. 40-41), Steve Anchell suggests that 250 ml of undiluted developer is the bare minimum to develop 80x80 inches of film (e.g., 1 roll of 36 exp. 35mm), but suggests adding an extra 100 ml per roll. When the developer is diluted, he has a formula for further developer volume. I find this suggestion troubling because of the effective reduction in the number of rolls I can develop in one tank (e.g., 2 rolls per 4-roll tank).

Is anyone following this advice and have you noticed a meaningful difference in your negatives?

Also, I am not sure how this advice relates to developer capacity. It seems to be standard practice to toss developer that's been diluted, but to reuse developers such as D-23 that is used undiluted. But if one is trying to maximize developer action, perhaps even undiluted developer should be discarded, because the developer's effectiveness per square inch of film is reduced?

The specific developer in my case is D-23. I just mixed a batch from raw chemicals and am getting ready to use it for the first time.

I appreciate comments and advice. Thanks!