Bill, thanks for explaining the "aft CG is faster" premise so clearly and concisely.

As for why I was moving heavy cargo, it was a passenger who needed a bit of privacy for a few moments. Upon realizing that the extra speed would get us to our destination nearly 45 minutes ahead of schedule, and he was in no way interested in taking the controls, we decided that he should stay in the back seat for the duration of cruise. He came back up front prior to descent.