Ok, if others have contributions in terms of the working strength life time, I would gladly hear them...

Tom's detailed answer with recipes raises another question though:

- How do these WT/CT developers actually work???

I mean: silver is silver? :o

How can a developer actually change the "tone" of the print??? What is the chemistry or physics behind their workings? Is it a change in the size or shape of the silver particles? Or are there actually more substances deposited than just plain metallic silver in a silver print??