Ferris, I agree that the present situation of differing SOPs with regard to TCAS RAs with different operators is fraught with danger but the sooner a unanimous agrement can be hammered out, the safer we will be by following TCAS RAs. Ueberlingen being the latest example and a personal experience, many years ago, of being cleared to 10,000ft Onjuku VOR on approach to Haneda, only to have our windscreen filled with the view of the under belly of a JAL 747 departure cleared to Onjuku at the same level on a different frequency. That was before the days of TCAS.
To quote from TCAS Pilot's Handbook:
Pilots are authorized to deviate from their current ATC clearance to the extent necessary to comply with the TCAS Resolution Advisory (RA)