It is very likely that the square load theory was developed by a mathematician and not a shooter. Equal length and width of a charge is a reference point for optimum stability. While stability may be poor, it is still better than any other. If it is not, point out the superior relationship.
It is just as easy to say that a solid lead wadcutter bullet has set back, deforms, and acts as a FLUID while moving down the length of a smoothbore barrel. It still has a predetermined weight and a balanced center of mass. All of the other factors offered are external... particularly choke coning.
Unlike others here, I never watched Harry Potter. But if you have a fluid charge or a solid charge that is more stable than square, this is the time to trot it out.
