> What I'm *really* interested in is a head-to-
> head test against a "resistored" bulb ... (already
> *knowing* all the factors involved ...)

I'm sure the bulb manufacturers have that data. Whether
you can get it is another matter. A reasonably small test
sample might do, maybe a dozen bulbs and a PIC to run
the switching. My guess is that a combination of resistor
+soft-start (electronic or using an in-rush suppressor)
would extend the life-time of a bulb 10's of times for very
little outlay. If the bulbs I've got resistored popped today
I wouldn't care - made my money back many times already

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