Ask anyone who has lived/worked in different time zones and the answer to this is "no". Humans are awake during the day, so it makes sense to have a system that identifies when daylight occurs in any given place. Otherwise, if the entire world has the same time (i.e. 4am now in all places worldwide), you lose that indicator of daylight. Hence, I would have to rember unique working-day (daylight) times for all places worldwide when I'm working and that shifts the information burden in the wrong direction.

I'm with you. The system, as it stands, is suboptimal, but it's pretty good. If I want to call my brother in Hawaii, it's easy to subtract 5 or 6 hours (HI does not observe DST) and know immediately whether it's a good time to call.

As far as the suboptimal aspects go, DST isn't very nice, and AM/PM is a bit superfluous in the age of digital clocks (compared to 24-hour time).

Ask anyone who's lived/worked in Antarctica, and they'll you that humans still sleep when the days are 24 hours long and still wake up when the nights are 24 hours long.

If you really want time zones that tell you when the sun's out, they'll have to be defined latitudinally as well as longitudinally, and they'll need to vary over the course of the year.

One change that I do think would be for the better is to replace the names of time zones with explicit references to/from a standard time to make it easier to compare different locations. As it is you have to stop and look up conversions for zones you are not familiar with.

we really do NOT need 4 times zones in the US. Why not consolodate to 2 (China spans 5 but standardize on one zone http://en.wikipedia.org/wiki/Time_in_China) I am not one of those people that thinks every China does is groovy, but in this case they are on to something. I think that there is more comercial benefit to 2 time zones in the US that we get from daylight savings time, the time for which has come and gone. Why not just have East and West TZ's?