The ingredient that gives the powder the energy/power is Potassium Nitrate. OE uses less than Swiss. Yet, you get more power with OE.
The Potassium Nitrate is just the oxidizer.
The Charcoal is the fuel.
How the charcoal is made, what it is made from, how long and how the three components are milled can make a huge difference in how the powder performs. I find it interesting they use one MSD for all the powders. When I started shooting BP the only powder we could buy was military fuse powder packaged as sporting BP or in the case of the C&H being imported basically a blasting powder grind. It was impossible to get the ballistics from cartridge guns that would match the 19th c figures with the same charge weights. It had the wrong charcoal and was only milled to make the military spec for fuses and boosters. I suspect that the military is still their major market. For example, every hand grenade has a BP fuse.
To make a BP equal to the best being made in the era from the Civil War (at least) on requires the right wood, even cut at the right time of year, CAREFULLY charred, broken up, then milled with the other ingredients for a longer time than the lower grade powders.
If you read Ned Roberts "Muzzleloading Caplock Rifle" you will find that the serious shooters only used a few powders, C&H Diamond Grain, Hazzards "Kentucky Rifle" and one or two others. In the late 19th and early 20th C as blackpowder was falling from use Dupont bought up and destroyed all the powder mills in the US. Since, SFAIK, Dupont never made a powder as good as "Kentucky Rifle" the premium powders vanished. Since the military became the main customer they built powder that would meet that spec. Which was not all that great. This remained until Swiss and the other European powders came to America.
Now when I hear of people having blackpowder turn to soup in the pan while hunting, for example, I wonder if the rifle is clean (fouling will suck up water like sponge and wet any powder it touches, good blackpowder will not suck up enough water from the air to fail to fire. However, at Moosic for a long time Goex was using impure Potassium Nitrate. This did not change until the supplier went out of business. Impure PN will cause moisture issues.
Nor was it wheel milled to a particle size that gave best performance. While graphite allows a poorly finished powder to look better and will prevent clumping the the British military would not accept any powder treated with "black lead", graphite. Remember that British War ships sailed all over the planet with ammo stored below the waterline. Powder that was not properly made would make the ship combat ineffective.
NOW consider this.
The powder made in the US at the time of the American Revolution was, by the standards of Swiss, generally very poorly made. It was almost all "stamp mill" (think giant mortar and pestle) mixed/ground powder and the use of presses and breakers was uncommon everywhere. In the mid 18th c a most powder was not press cake powder but simply forced through screens, by hand, to form the granules.
So almost any powder we can buy is superior to that used by Daniel Boone for most of his life. So using Swiss is "not traditional" until at least the late 18th and early 19th c.
However, my Nock patent breech rifle will not function with a powder that forms flakes of powder fouling, in a shot or two it will fail to fire. I ran in to this with Schuetzen when I tried it. So I only use Swiss FF. I never bothered to try anything else. What does this tell me? It tells me for the 1787 Nock breech to work without any hair pulling a pretty good powder was needed. Better than much of what we buy to day.
There is no easy answer to this. But I do wonder how GOEX can make a powder that is supposedly better than Swiss and sell it cheaper unless there is a significant tariff in the European powder.
This is all knowledge based for the most part on research by the Mad Monk, Bill Knight, who over the years has been kind enough to share his finding with me.