This is a conversation I have on every flight with a pilot-rated passenger. I often fly with other CFIs, ATPs, airline guys, fresh PPs, you name it. Often I'll give them stick time, but if something should happen, they have to be OK with the fact that if an abnormal situation arises, I'm taking over--no questions asked. It's my plane, a fly it a lot, I try to maintain a high level of proficiency, and I'm always anticipating an emergency--regardless of who's doing the flying. I even briefed this on a checkride with the DPE: yes it's a checkride, and yes I am PIC, but understand that if there's a REAL emergency I do not plan to relinquish the controls to you; I will ask for your help, but I will fly the plane to a safe landing. Are you OK with that?
Conversely, on my last MEI checkride a couple of years ago, the preflight briefing with the DPE went something like this: yes it's a checkride, and yes I am PIC, but understand that if there's a REAL emergency on this flight, I have full confidence in my ability to respond to the emergency but I also have 15 hours of multi PIC time and just began flying the plane two days ago; you have closer to 15,000 hours and two decades of experience; I will respond to the initial emergency but I may ask for your assistance flying the airplane, using the positive exchange of controls protocol (briefed previously). Are you willing to do that if asked?
In both cases the DPEs were agreeable to my proposition.
