I think single entry/single exit is very valuable, and worth a bit of clunkiness for. And the branch version is also pretty clunky: either the long-winded "return ", abuse of "and"/"or", or the weirdly backwards expression version of "if" that Python has.

I don't disagree that branching on bits is clunky. That it's still less clunky than using Church or Scott-encodings speaks volumes of the practicality of the latter.