Each firearm is an individual. Some shoot better than others. Often, what shoots well in one shoots so-so or poorly in another. This is true of all guns, not just cap and ball revolvers.
I've been shooting cap and ball revolvers since about 1970. I posted, "So you want a cap and ball revolver?" because it put together a wealth of information in one place; information that took me and others years to discover, or rediscover from old-time sources.
I don't consider it a waste of time, or B.S., to pass on experience garnered over decades.
If you revolver delivered groups of "3 on top of one another on the bullseye, first try," then you have an exceptional revolver.
Certainly, it's not the norm from what I've experienced, seen and been told by others. Every cap and ball revolver I've encountered shot above or below a bullseye at 25 yards. The Colts typically shoot high; the Remingtons typically shoot low.
You were very lucky to find such a gun that hit dead-on at 20 yards the first time. It is not the norm.
"And lo, did I see an ugly cat. Smoke. Brimstone. Holes in parchment. And this ugly cat was much amused." --- The Prophesies of Gatodamus (1503 - 1566)