While this is easy to implement at first, it leaves a usability bug for users who do not actually want to use it... (what should it be by default?

By default, it should perform exactly the way it currently does. Then you have an added feature at no cost to those who don't want it.

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Believe nothing, no matter where you read it, or who said it - even if I have said it - unless it agrees with your own reason and your own common sense.
-- Buddha