Caffeic acid is a close cousin of catechol
So a pyro developer (commercial) will work more or less the same

Adding vitC increases the activity/shadow detail and lowers the stain
it if is cheating... so what?

I really think commercial versions would be no fun

Quote Originally Posted by cmo View Post
My assumption: it might become very popular if it were an improved, reliable, off-the-shelf product.

Simply because it is staining, but not toxic, and the results I have seen so far from Nescafé-and-Folgers homebrew stuff are quite impressive for such a simple recipe. With some experimenting and good scientific knowledge of photo chemicals it might become an excellent developer.