A discussion of barrel length without consideration of barrel weight and weight distribution is rather vague (almost pointless).

The weight is for carry and lift effort. Balance is for how the weight is distributed between the hands. The swing efforts are for the effort to point the gun in a differing direction. Note that neither barrel length nor LOP is a factor.

The further increments of weight are from the CG/balance point the more effect they have on swing effort. For those who do do math, the effect is 4X for double the length. Think of rifle bullet energy vs velocity, subing swing effort vs length.

DDA