I have recently measured negative densities on the blue channel of a color densitometer. The pyrocat stain will add about .30 density over what the visual reading would be at a 1.20 density. This is important to note since it will be a factor when contact printing on Azo.

Additionally the times that Clay Harmon and Sandy King have been kind enough to share appear to be very accurate in my experience. The difference in my processing compared to theirs is that they use a Jobo and I brush develop my negatives (thanks to Jorge).

The negatives that I took the readings on were processed in acid stop bath and conventional hypo. Both of which were mixed as normal with no special considerations given for the pyro stain.

Hope that this is of help.