I also doubt a study would prompt any change, and it is nice to have the extra light, especially the further north you get.  But isn't it still up to each individual state?  I believe Hawaii and Arizona are the only states that don't use DST.  With all of the growth (and sun) in the southeast and southwest, it makes sense for those states to get rid of DST to save money and energy, but states up north to keep it since the day is so noticeably shorter.

When I lived in the Sacramento valley, I would have much preferred to forgo daylight savings time. We had (and still have) toxic photochemical smog produced by sunlight acting on exhaust fumes. With DST, there was no way to exercise (including cycling to work) prior to the great onset of commuter exhaust. Had we ditched DST, people could have been active outdoors in the lighted hours prior to the onset of the workday and done so while breathing much lower levels of lung-damaging ozone. Who knows, experiencing the outdoors in the absence of the worst air pollution might have even caused some people to place some value on our shared environment.