Excellent arguments, gentlemen. All very important points either way. It really doesn't matter, though, as this piece is hardly a put-together or blacksmith rendition. The 'could be' might never be fully answered, but this sword is so magnificent, who cares at this point! I have never looked down on colonial pieces (NOT saying this is one) as they are an important and integral part of the big historical picture.
Going back to the screw-tang, did we ever determine when this practice was started? Obviously, screws have been around since the Middle Ages and many components of armor possess said attachments. I know Scottish basket hilts with 'screw' pommels started appearing in the last quarter of the 18th century. Many of the Dutch pieces circa 1700 had the off-set screw/nut attachment for the knucklebow.