Edward Todd enameled pen puzzle

This Edward Todd came to me recently, bringing to three the number of similar enameled ringtops sitting around the shop (one was profiled here last year). Unlike the other two, which are both lever-fillers, this one is an eyedropper-filler. Like the others, it is fully marked on the end of the barrel. But while the others came with their apparently-original Edward Todd nibs, this one had a Wahl Tempoint nib instead. My first impulse  was to dig out a suitable Edward Todd nib to swap in, but then it struck me that the section profile wasn't right, either, as it was identical to that found on early Wahls and their Boston precursors. Ditto for the feed.

But wait: this pen is an eyedropper, so if this were a Wahl or Boston section, the section's threads would have to match. Yet after digging into my store of Wahl and Boston eyedroppers, I found that the threads don't match. Their dimensions are correct, but while the Wahl and Boston threads are all single-start, the Edward Todd's threads are triple!

From top to bottom: Edward Todd lever-filler, Edward Todd eyedropper, Wahl eyedropper

Why anyone would use triple-start threads for an eyedropper's section joint is beyond me. It makes opening and closing the pen marginally faster, but at the cost of increasing the risk of the section coming unscrewed unintentionally. In any case, there can be little doubt that the section now in my newly-acquired pen is the original. The threads are one indication; the other is the Edward Todd lever-filler shown at the top of the picture above, whose section (press-fit) has a similarly Wahl-like exterior profile -- though the feed is simple and unfinned. So I'm not going to do any switching of sections, feeds, or nibs, though I am now wondering if Edward Todd was purchasing hard rubber components from Wahl or Boston. If so, that still doesn't explain the presence of the Tempoint nib, since Edward Todd consistently used own-marked nibs throughout the company's history. Just a coincidence, a Wahl nib put into a Wahl-made Edward Todd section? If any readers have any other data points, please let me know. I have several other non-enameled Edward Todds somewhere around the house, and when I locate them I'll check to see if any have similar sections or feeds.

NOTE: While Mabie Todd sections can have a similar profile -- a cylinder, a conical taper, and another conical taper -- the cylindrical part is markedly wider than on the Wahl and Boston sections, and the transition between the cylinder and the adjoining taper is generally more rounded.