I think one problem is he doesn't, or at least it is managed through heroic effort as opposed to efficiently. Updates take longer and longer and have a longer period of 'everythings broken' as the game progresses. From all reports the code is a complete mess. It's an amazing piece of work, but it does seem like there is some wasted potential there (though I can believe that it may not be possible to harness that potential without giving up on the incredible ambition of the game, because this is the kind of thing that can only really be accomplished by someone who is completely unreasonable).