Well, the solution here is obviously to make things fast, so that it never takes a long time.  I am convinced that it can be done.  We just need to figure out what is slow, and how to make it faster.  

And anyway, my philosophy is that if it is off by default, then it might as well not exist, because 99% of users will never know it was there.  I also believe that it's better to have a slow function that returns a solution than a fast function that doesn't.  So I think even if it is slow that this should be True by default.