In any case, my original mistake was using an extremely low dilution of Pyrocat HD on Classic 200 for a scene that really did not need it. I also underestimated the time needed for the film to develop at such an extreme dilution. So far it seems that Classic 200 likes the 2:2:100 dilution much more than the others I have tried (1:2:100, 1:1:100). Does this mean that Classic 200 is an excellent film for PtPd?