Played a couple of times with a real caddy. Several were real good dudes that kept things light and if they were a real caddy at the course, their green reading was outstanding. My score easily would have been 5-8 shots higher without their greens skills.
TPC Harding Park is CPO. Massive pain, but when I played it I still had some lingering effects of knee surgery, so I wasn't ok to walk it.
Played TPC Scottsdale years ago. On the first tee, our fore caddie rearranged the clubs in my bag. Really threw me off since he wasn't pulling clubs for me. Again though, green reading was fantastic.