I have 15 or so rolls of HP3 and FP3 120 that my late ex-father-in-law had shot around 1952 and never processed. The backing paper sticks to both sides of the film, so that it does impede processing if not removed first. I may try getting as much as possible off, then loading the film plus paper blotches in a SS tank, and soaking overnight, then squeegeeing in darkness, then reload and develop. The ones I tried without doing this did have images, but marred by the sticking paper.
FWIW, I also had a bunch of 2x3 glass plates from around the same era that he never processed, including a batch marked "coronation" that actually produced images. It was an excitement to see those! Almost like going through a time machine.