Dawes man,
Splendid bike. I have no idea, just to be up front, but if I may hazard a guess you may find completely obvious ...just because I like a good engineering problem? To get that splitter collar on after the cables were crimped together, the assembly must have been assembled in pieces and those lead cable ends, either the two after the split or the one, must have been crimped on or otherwise attached after all the pieces were put together. My guess is the single was put on last. How, I do not know. I know, probably obvious, but...how did they attach those ends?...cast in place? ...more likely a heavy form press. ...and how to take it apart without cutting the cable end off? I don't see a way. Interesting.