Correct me if I'm wrong
Gladly. I think it comes down to the following:
- It eliminates ambiguity. 0900-1700 has exactly one meaning, globally.
- It eliminates the need to do timezone math. (I.e. They say they're open 9-5. What do I have to add/subtract to turn that into my time?)
Whether these differences are huge or minor, and for whom, will depend on various factors, but I believe that they'll be very significant much more than they'll be insignificant.
I think one test of whether the proposal would work is to look at how the scheme is already being used. There are organizations already who run exclusively on UTC. How do they fare?