I was staring at my bike this morning and realized, hey, the seat lug and bb lug have cutouts exactly where the oval shape windows in the spearpoint lugs are (see pics below). So I looked at one of the spearpoint lugs where the paint is worn off and can see a very faint line where the point was welded to the lug. The oval window would have been half from the lug and half from the extension. Mystery solved; thanks for the help and information!