I still think it is a question of chicken and egg. Following the thought process here, chambers were 2-1/2"; ammo makers lengthened shells for more performance to 2-3/4"; someone ran some cursory tests with pretty little data collected and pronounced the that long shells in a shorter chamber gave better performance; gunmakers after bragging rights decided to shorten the chambers to take advantage of that performance; ammo makers shortened their new shells to stay safe.
That's a lot of changes with little real data and even less factual proof that is what happened.
What is true is that in a later era with the proven performance of one piece cup wads, performance was elevated to an entirely different level and then improved again by modern design of barrels with long forcing cones and overbored barrels (which shouldn't even work based on the original theory). Trap shooters led the way and today no one builds a high performance shotgun without those features. The same features worked just as well before the plastic cup wads. Look at the work done by Becker and others and the legendery performance of the NNID Ithaca 10's and the Super Fox. The Parker was ahead of the times and normally used overbored barrels in their 10 and 12 guns, many of which performed very well with cylinder bored barrels.
The fact is that a long forcing cone with it's very shallow taper gives a smoother transition and the overbored barrel drastically reduces the effect of scrubbing on the shot column.
The proposition might make for an interesting history discussion (although proven details are nebulous) but they are neither here nor there as far as modern performance is concerned. Shoot appropriate shells the same or lesser length than the chamber and loaded with modern components, and everything will work well.
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