let me clarify. I was recommending Brian try Pyrocat HD not to boost contrast but as better suited to rotary development. Rollo Pyro, despite it's name, often gave me streaks in my negs in a Jobo, pyrocat never has.
I think my exposure technique, i.e., expose at 1/2 manufacturer's ISO and place shadows on Zone IV, is more than generous. I believe you can always "throw away" shadow detail when you print but you can never get it back if you under expose.