I've read those paragraphs at least a dozen times since I first saw reference to the "flip-flop operator" in the spoiler for an obfu, one of erudil's or maybe on of yours, and I still have trouble applying it.

If anyone has a less wordy, more .. um .. transparent description of the .. and ... in a scalar context, or even better a simple example of use that is self-contained and demonstrative, I for one would find that very useful.