Matthew, in short, yes.
In a cinema, you're running the same reels through the projector over and over. There's little time to clean each film before/after running it, let alone doing the same with the PTRs. If you don't clean both, then dirt is going to accumulate beyond what the PTRs can remove. Thus, even clean films will get dirtied up. I guess no matter how clean your film and PTRs are, there's always a chance of just re-depositing dirt as well.
Unless someone is using their Kinograph to transfer films constantly and they're not willing to prep the PTRs and film, then I'd assume using PTRs in a Kinograph can't exactly hurt.
I'll also throw out that some of the AVISynth scripts are pretty darn good at cleaning up dirt/scratches in post. Granted, you're estimating the necessary fix, and it can lead to some odd artifacts or incidental removal of valid information.
I'm sure everyone would agree the best place to remove dirt is before the scan. So to summarize methods:
- Use Filmguard cleaning solution prior-to or during running film (could be manual or using an automated system/attachment.
- Use of air blowers and/or anti-static brushes just prior to film entering gate.
- PTRs to physically remove dirt
Everyone would have to make their own evaluation of what to use based on their needs.