@tallbackhip

I believe both of your points come down to having a superbly skilled revision surgeon. Revisions tend to be more complex than original replacements. Not all hip/knee surgeons do revisions and of those who do, I would trust very few to do a revision for me. Most revision surgeons also do original replacements so I consider their experience in both areas in forming my judgment.

My incredible surgeon (replaced my left hip and my right knee with no post surgical pain each time) devotes about 20% of his time to revisions.

In my view what I would call centers of excellence (such as Mayo Clinic, Cleveland Clinic, Scripps Clinic, Hospital for Special Surgery, etc. have a very high standard of excellence for all of their staff. The absolutely best surgeons are usually outside of these centers but locating them is more difficult. I looked at research papers, orthopedic conference meetings, etc. to try to narrow down the selection.