The analogy of a figure skater is often used.

When a figure skater wants to spin fast, she pulls her arms in. To spin slow, the arms are extended.

If the frame of a shotgun could be made a point mass at the center of gravity, it would rotate about that point very easily.

Stretch it out like a Krieghoff or a Winchester 21, and it rather resists rotational movement.

Powell has it backwards as far as comparing action types.

"The price of good shotgunnery is constant practice" - Fred Kimble