Yep.
Nope, unless you are an ATP in an ATP operation.

Are you arguing about what the regs say, or about the "reasonableness" of the regs?

I would say that if you are demoing to a student for any time other than a tiny portion of the flight (less than a tenth of an hour) TO SOMEONE THAT IS ALREADY RATED IN THE AIRCRAFT, then:

1. Technically, according to the regs, he can't log the entire flight time as PIC.
2. If you are doing a demo to a rated pilot, of any maneuver that takes more than about 30 seconds, that's pretty unusual.

We aren't logging time to the nearest second, so the usual practice of "rounding" the rated student's "sole manipulator" time to the nearest tenth is reasonable.

We were talking about this "ATP operation" the other day. What is it? I've never heard of it.

See FAR 61.51(e)(2); I don't know any more than that.

Ah............i get it now any operation that requires an ATP aka 121 flying.

No. The private pilot must manipulate the controls to log the time as PIC. Dual given is not PIC time, just "dual given" in the instructor's logbook, and "dual received" in the students logbook. It has nothing to do with logging PIC time as stated in 61.51.

Not if you are an ATP. Only a sport, recreational, private, or commercial pilot may log PIC as sole manipulator for an aircraft for which the pilot is rated.

I can tell you that while during an interview for an operation looking for Part 1 PIC time you will have to explain why your PIC and SIC swap legs. Log it as you wish it just depends what your end goal is. I have never had a corporate interview that required Part 1 PIC. Most insurance companies use Part 61 PIC to meet minimum standards.

got to agree with DSflyer05, we operate about the same exact way. log what you want, just be able to explain yourself as something more than a time-padding right seater

Sometimes 121 can be a beautiful thing. No worries over this sort of stuff just CAs & FOs.