The problem in these discussions is that people over-rely on physical intuition when dealing with populations, instead of math, specifically, statistics. At the physics level, an obvious difference in bullet drop or wind deflection or energy or cross sectional area or any other number of physical parameters often is of limited significance when discussing population effects. We see this all the time in pharmacology: some new drug has much greater receptor affinity than the old standard, or much better chemical properties, is promoted by the drug company therefore as as a dramatic advance—and in head to head population study in clinical trials there’s no significant difference in outcomes. The South Carolina Study is a good example. Out in the real world of deer populations, the different physical parameters of one caliber vs another were not statistically important because there are too many other relevant variables and confounders.
All of which is why, as a physicist, I've programmed models and simulations to see the statistical impact of varying certain ballistic parameters, and as a hunter and competitive shooter I've seen, first-hand, the difference that small changes in various parameters can make in the ability of a shooter to intersect POA and POI. The ability to predict POI is a dependent variable that has a particular uncertainty associated with it, which is really the propagation of other uncertainties associated with the independent variables involved. If the shooter's skill is by far the largest source of uncertainty in POI, then of course reducing the uncertainty attributed to the other variables (like wind drift, drop, etc.) won't be distinguishable in the results. The study from South Carolina was mainly focused on terminal performance and not external ballistics, and included guys with probably average shooting skill. In order for some of these ballistic advantages to become significant, a shooter must develop the skill to exploit those advantages.
All that is to say that if a hunter can't shoot well enough to place his shot in vitals beyond 150 yards, then there is no way he'll be able to resolve trajectory advantages (whether vertical or horizontal) at 300 yards. But for those who put in the effort and investment of time and money, those advantages can become material and significant.
