Repeated shooting as in competition, in warm low humidity weather, is one true test of patch lube. In theory, the downstroke of the wet reloaded patch and ball, cleans the bore for each successive shot...this is where home concoctions of Murphy's oil soap/water/alcohol, whatever, really perform. Several guys I compete with have gone to a household cleaner "Simple Green" 20% green/80% water, and are happy with the results. We often shoot timed events, in as rapid fire as you can with a muzzleloader, and if a gun is going to foul and become difficult to load....you are pretty much toast, and your team will treat you like the red headed stepchild. In a hunting situation, where the gun may be loaded for days without firing, grease patches of course, rule.
Accuracy? I have had guys frequently put 5 in 1 1/4" at 50 yds under ideal conditions. I know of a Browning .54 with a Sharon barrel that has gotten 5 shots touching at 100 yds, more than once. When a guy brings me a gun (got a well equipped range in my yard) for help developing a load, in spite of his protests, I start a .54 at 60 grs and shoot groups increasing 5 gr increments until it starts to open up. Accuracy trumps velocity...a 224 grain ball with a frontal area of over .54 is a reliable no drama killer.
You sound like a pretty savvy shooter...just pay attention to the little details which will make 'good enuff' into great.
