I have personally off a bench rest at 100 yards shots some groups well under 1". In other words all three shots touching. My trouble is the next time at the range it might shoot a 2" group or because of a flyer even worse. So yes, the small groups are possible like you said bigcountry. I would never say that I can do it each and every time I go to the range. Some days I swear I have never sighted in the rifle it shoots so bad.
I also shoot a lot. And I shoot a number of different rifles. My best rifle by far is my Thompson Center Black Diamond XR and then my Knight Wolverine. I'd hate to live on the difference between the two.
With open sights, I have never shot a 1" at 100 yards with any of my muzzleloaders, but I have shot some impressive groups with them also. I understand what your saying....
Ding, ding, ding. Finally a man with experience, integity, and honest with himself and fellow shooting buddies who we all can learn alot from.