The Present Northern Line

Just after the First World War, we know that the CSLR was running between Euston and Stockwell, and plans were being formulated to extend the line to Morden. We also know that the CCEHR ran between Golders Green/Highgate to Charing Cross, with plans to extend to Edgware, and that the Bakerloo line ran between Watford Junction and Elephant & Castle. So it seems to me there were several different possibilities for the newly-formed LER to chew over. One would have been to extend the CSLR to Camden Town, take over one of the branches of the CCHER, but keeping them separate; another to extend the CCHER to Kennington and beyond into South-East London, also keeping it separate from the CSLR at Kennington; another to join up the Bakerloo line with the CSLR at Elephant & Castle. All of these would have resulted in a relatively simple operating structure, with at the most one branch. But instead, they opted for the most complicated: joining up the CSLR and the CCHER, which necessitated comlicated flying junctions at both Camdedn Town and Kennington. Granted, it offered a great choice to passengers at the extremities of the new line, both North and South - to travel either into the West End or the City. But did Lord Ashfield's team give a lot of consideration as to how complicated it would be to operate the new line, not to say potentially different traffic flows in all branches of the line? I'm interested in finding out who it was that came up with the present structure and how much consideration there was to other - seemingly easier - alternatives.