That seems like a reasonable analysis. I suspect the standard manufacturing mantra of "how can we make it a little bit cheaper" is coming into play.
Reducing costs by using cheaper materials (and often less of them) coupled with "innovative" ways of assembling them results in parts that often have correspondingly higher and higher failure rates until market feedback forces the manufacturer to backpedal a little. A glass envelope a few microns thinner doesn't seem to be a big change, but as you well know from your industrial days, even very fractional costs add up when you're making 10's of thousands of something. I've had a number of bulbs that have cracked at the base recently so I assume something's been "economized" in the manufacturing process.
Of course, there are always plain old manufacturing defects, which I expect to be rising as fewer workers are expected to do more and more as companies strive to satisfy investors first and customers last.
Even if a CFL has a good warranty, there's a cost associated with having a manufacturer make good on it. A defective incandescent bulb costs a quarter and goes into the trash if it fails. A defective CFL that has to be returned involves postage costs, time costs, etc. Usually it means the bulb gets dumped because it costs just as much to screw around with warranty replacement as it does to go out and buy a new one. As you pointed out earlier, X-10 users of CFL's have to factor in the cost of filters so the equations have lots of hidden inputs.
The most serious defect in relatively simplistic equations like Wikipedia's for predicting bulb costs is neglecting the spill heat produced by incandescents and the effect that has on heating and cooling bills. In many cases, it could be a wash, but that's not guaranteed, especially in my case where I use more CFL's in the summer than the winter. We're more willing to deal with the problems of CFL's in the summer where they keep the house cooler and the electrical bill down during peak rate hours.
In addition, it's hard to put a dollar value on things like:
the nuisance of slow warm ups, shifting color temperatures, inability to work properly outdoors in very cold weather, buzzing, flickering, interference with HA devices, bulbs too big to fit in standard reflectors, bulbs that extend beyond standard reflectors
and some of the other issues involved with replacing incandescent bulbs with CFL. They all factor into the decision of whether to use a CFL bulb or a incandescent. So does something as simple as how many times a day a bulb is cycled. We still use incandescents in places like the bathroom where lights can be turned on and off 20 or more times a day. CFL's positively wither under such usage while long-life bulbs seem to take it in stride.
-- Bobby G.