Afternoom, Roy, mon vieux - yes, I DO shoot Pyrodex, but only in my revolvers - solid bullets, too, not with a whacking great hollow base and fragile skirt.
You have it absolutely right - shooting Minies, BP is all you should be shooting.
Shooting solid conicals, like a .54cal Hawken or similar, with whopping loads of around 90 - 110gr of RS is just fine, if you really have to, but I use only BP in MY .451cal BP rifle.
Besp
tac