I've since thought of and tested more examples of how the back button does work perfectly fine, but I won't get into it.
What Straus wanted -- where the back button returned to whatever was the previous screen no matter what, even if it was a separate app -- would also put us in an infinite loop. Pointing this out should have been the end of the conversation. So even if the current implementation of the back button is, once in a rare while, funky, Straus' idea for the back button would have truly been bizarre, regardless of his [false or inapplicable] analogy he kept bringing up about traveling to and from highways.
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Here we go again. Heh.
Again, Straus, you should be glad it doesn't. Taking you back to the last screen, no matter what, would put you in an infinite loop. I gave you many examples of this. How do you reconcile that in your Android-world where the back button does that? I really don't get it.
Oh I didn't notice that it does bottom out at the home screen. I don't think it would be a bad thing to have an infinite loop at all though, but at the same time I don't think it's a big deal in the least. I think if there was simply a setting, like there is for looping thru your home screens for example.