"T o d d P a t t i s t" wrote:

I have seen a written interpretation by the Chief Counsel
stating that the only pilot on board can log PIC time when
allowing other non-pilots to manipulate the controls. The
reasoning given was that the only pilot on board was the
PIC, followed by some handwaving and references to
definitions in the FARs.

I've never heard of this, and don't see it in my copy of Jeppesen's "FARs
Explained". Do you have the reference?