Really? I haven't investigated the Bronica lenses much, but I'd particularly like to get the 50mm working. Thanks for reminding me of this thread - I had planned to find where I've hidden those lenses, now I should be able to remember to do it.
I posted how to do it in photo.net a long time ago. I describe how to get in to the trouble spot. Then it's clean and relube sparingly with a thin grease. The method's the same for the SQ and ETR lenses.