Just got back in from printing some HP-5/Pyrocat negs in palladium!
Sandy and I have been corresponding on the Jobo issue, and I am now a total believer - the slower the better with pyrocat. It is not prone to streaking and uneven staining to begin with, so the the slow speed should not be a problem. What I was experiencing with higher speed films such as Tri-X and HP-5 was that the spent developer was almost muddy brown when I dumped it from the jobo, and the film rebate (edge) was stained a brownish/pinkish color. My printing times on some negatives was pretty long. Sandy suggested that too much aerial oxidation might be occuring due to my using the Jobo at the "F" setting, which is supposed to be the film setting. So I re-ran some tests for HP-5 at the 2:2:100 dilution and the absolute slowest speed setting, and voila - the problem disappeared.
I have the test data and will post some times if you tell me what process you are using so I can use the proper target density range for your ideal negative. Coincidentally, Sandy also now recommends a full-spectrum (all channel) target density range for palladium at 1.3. I now concur with that heartily. My best print from the latest batch had exactly that range: shadow values at .25, highlights at 1.55. This also happens to be the perfect Azo/Amidol grade 2 density range. So you can have your cake and eat it too!