1874sharpsshooter
While I have no scientific evidence to support my thoughts either, the majority of people I talk to have never shot more than 2 different bullets in their MLs. They simply shoot what someone told them to shoot.
So to your point about fast twist .45s (or any other "Proprietary" guns) it seems the simple solution is to include the proper bullet for that gun with any purchase. When the individual buys the gun, it comes with 2 packs of __ bullets which are designed for fast twist .45s or the .52 or a .57 cal... This way the gun shoots with the projectiles designed for it. Heck CVA puts those crappy powerbelts in with their guns and people shoot them like crazy.
We here on the forum seem to think that people are like us who test different bullets/powders/guns and primers are normal when in fact, we are a very small portion of the muzzleloader shooting community. To this day, I am still the only one I know personally who hunts exclusively with a ML.