Thanks, and yeah to the other main point in this thread re: transporting other members of the business there is another interpretation which makes it pretty clear.
Search the "Lamb-2" interpretation from 2010 (I am too new to post links).
Basically that if you transport yourself for something incidental to the business, but for a business reason, it's fine and you can be reimbursed by employer. If you bring pax, however, you cannot be compensated at all and must pay a pro-rata share. Pretty much black and white. It's hard to argue against, too, since the business is literally giving you money to bring their employees somewhere. Even if you would go on your own anyway, things change once people get in the plane. I think that makes a lot of sense since without that rule it would be very easy for a business to put pressure on the pilot to transport its employees places and at some point you are some percentage an employee of the business and some percentage being paid as a pilot.