Great another rat hole for me to venture down. Troubling that in everything I've read by the masking gurus (Burkett, Bond, Radeka etc) I don't recall ever seeing any mention of this variable in chosing the masking film. They all use and recommend a variety of films from TMax to FP4 to Ortho Plus to various slow ortho/litho films.
See my post #9. Many sheet films are coated on Estar to enable masking and other critical processes.