I Teflon-taped Rocky's top burr carrier ~ 3 years ago, and have replaced the tape once. My experience is only one "not data" point. Before taping, Rocky's hopper wobbled slightly while grinding. After putting 3 wraps of Teflon tape on the upper burr carrier, there was no visible wobble. The tape has clearly taken up slop in the threads. I think it has helped the consistency of my shots, but with all the other changes I have made to my setup, who knows?
I Googled for one of the earlier threads on which Teflon taping Rocky was discussed on AC -- interesting reading for a Rocky owner considering this mod.
Rocky Problems since Burrs Replaced
Rick