[American Viking]

I disagree with your statements that pre-obdII cars more polluting..

OBD II protocols are biased to keeping the catalyst hot, at the expense of mileage and efficient combustion. In fact if you make a modification that reduces the emissions significantly, the computer will enrich the mixture to extremes to get exhaust dirty enough to burn in the catalyst.
That's just a gross waste of fuel.
Its actually easier to tune an engine to run clean enough to not need the god awful catalytic converter at all. And don't let the EPA tell you that it cannot be done, it can.

I'm not big fan of the crazy lean burn engines either, but I like to be just a bit leaner than stoichiometric ratio.

If these hybrids and the new ICE's that shut off at traffic lights, either have to some quick heat-up protocol (either a shot of raw fuel directly at the cat to flash it off, a blowtorch hot air injection just ahead of the cat to thermally kick it up, or an electric heater built into the casing & honeycomb matrix) or they must have some exemption from the startup flash-off time. It used to be called the 240 (second) test.