On Sat, 7 Apr 2007 08:28:07 -0500, "Anthony Fremont"
Gave us:

Like always, they will be operated at the maximum power dissipation that
gives a life expectancy just longer than the warranty period. Why do you
think it would be any different? Just look at regular light bulbs, a 10%
reduction in voltage greatly increases life expectancy. Given that, it
stands to reason that manufacturers could just make the filament a little
sturdier to accomplish the same thing. Why aren't any manufacturers doing
that?


Most cars these days have halogen headlights.