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I'm going to disagree with you on the emissions merits of an ignition cut over a fuel injector cut.
The engine is going to turn over only a few times between when you hit the kill switch and when it comes to rest. An injector cut will save a few pulses worth of gas vs. an ignition cut. If you dump those few mg of gas into the exhaust and it doesn't get ignited, then you've created HC emissions. If it does get completely burned on the cat, you've raised the cat temperature a degree or two... but it's going to cool off a few dozen degrees anyway while you coast to a stop and wait for your light to turn green. The cat will get back up to operating temperature soon enough after you take off, no sense in pouring fuel on it to make that happen faster.
My Honda hybrid leaves the factory with auto-stop, wherein the engine comes to rest when it's not needed, and the cat begins to cool down. Yet the car meets with EPA and CARB approval.
As far as FI PW >0 during DFCO, huh. That's a head-scratcher. Are you sure? It kind of makes me want to measure it with a multimeter, not a scantool. The Scangauge reports that my Subaru uses 0.04gal/hr at 0rpm, which is clearly not the case.
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