Not only can humans not agree to have one standard time, they can't even have one consistent standard for when to change from one time to another.
...I'd like to take step beyond just keeping the time unchanged. I say we adopt GMT the whole world over. Everyone, everywhere would ALWAYS know what time it was. The only thing we would need to adjust to is eating at some time that would seem odd to us for a while. I bet we'd get used to it pretty fast....
-ERD50
Here's what we'll paint on the signs...
"Adjust Schedules Not Clocks!"