But here's the theoretical difference. Imagine there were a page called "The John Smith". If you used {{NameSort}}, you'd end up with a sort key of "John Smith, The". That would clearly be undesirable. {{TitleSort}} would instead result in the proper "Smith, John The}}.
No I'm thoroughly confused. Going back to using "The John Smith" as an example. You said in the first post that TitleSort would result in "Smith, John The" but your last post suggested that TitleSort would result in "John Smith, The". Which is it?