Ah of course, the NLE could then be depicted to cross the SWR line between Vauxhall and Waterloo, rather than between Queenstown Road and Vauxhall. I don’t think Geoff considered that in his video on the R&T map (I recall the suggestion to move Vauxhall down in the tube map, but the R&T map was implied to be insurmountable!).
I don’t see Nine Elms station getting much use anyway – if coming from the West, it’s quicker (and may also be cheaper) to use Vauxhall, and from the South similarly Vauxhall or Stockwell. Then again I think most people don’t care what fare they are charged, eg all the people at my work who get the train to Waterloo and then connect on the Jubilee line to London Bridge(!)