As for "temporarily" in section 463 referring to the unloading of passengers and merchandise, and not to the duration of the vehicle's "standing", you are correct, again. Give yourself a big pat on the back.
However, "standing of the vehicle" itself implies permanence. See cvc 587 for comparison. Webster dictionary does not define "standing" as a noun in any sense that would be applicable here, but one if its meanings as an adjective is " remaining at the same level, degree, or amount for an indeterminate period." So if the sign said "no parking", rather than "no stopping", and the O/P stopped to make a phone call or for other similar action of short duration, and especially if the engine was running, then his car was not parked. If you think he was parked, I'd be very curious what situation you do see as being stopped, but not parked. Do you mean the only such situation is when loading or unloading?
Another way to put it would be, if he wasn't pulled up long enough for the parking officer to write a citation, then he clearly was not parked.