Ive noticed that our model S gets confused with auto present and unlocking if both my wife and I are approaching the car and we each have a fob on us.
Oh, and I've created a driver profile that I call "garage" which I select after parking it. On my garage profile I disabled auto present and auto lock, so I can walk about my garage at will without having my car present and lock and present yet again...
That's a great idea!!
Lot's of great ideas on this thread actually!