Soooo...if you are being "checked out" on a brand new type with a 500HP radial engine up front (that is still only a SEP) and you are legal in all respects but never flown anything other than a C150, then it is ok for the RHS "PIC" to wrestle controls from the "sole manipulator" in the event of a botched approach and landing
Actually, no, in this case, unless the other pilot is an instructor then the "check pilot" is technically only there as an advisor - though as PIC you
can accept him taking control to save the aircraft - but that is down to you as PIC, in the other example you cannot be PIC so cannot be flying in the first place.