[num1]

You are absolutely correct there, once somebody has their commercial license it becomes easier and cheaper to build hours. I guess it comes down to how effective the practice is, as acrobatic maneuvers are frowned upon in most commercial settings. :P

Certainly getting your license doesn't mean you have mastered controlling the airplane, but I'd imagine that after a thousand hours of doing basic maneuvers and tightening your tolerances there's not much more you can do without buckling down and getting time in an acrobatic.