Lone Star - thanks for the update from the Cast Bullet Association, it makes sense when you add Veral's writings but I don't think my statements are mutually exclusive of his findings. Smith stated that your gun (barrel) has to be properly set up to avoid leading with oversized, soft bullets, which means the barrel needs to be properly lapped. I agree with this - if your barrel is properly set up (lapped), shooting soft bullets one thousands oversized should not cause leading.
I have lapped a number of pistol, revolver and rifle barrels and once properly set up they will handle all sorts of cast loads without problem, which is why I recommended lapping, as does Smith, for barrels that neither shoot as they should, or lead.
Did the information you cited by the Cast Bullet Association reference any points commensurate with Smith's findings???? It would be interesting to hear what they have to say about lapping. Mikey.