[rue]

I don't know which of us is “correct”, but I disagree with your opinion on the matter.

You're making an assumption of a standard time of day when stuff's open (I agree, 11:00 is a reasonable assumption). I can, however, make that same assumption. In your travel model, the traveler must know the timezone (and work with assumptions from there). In my mode, the traveler would need to know the “standard daytime hour” and work with assumptions from there.

So, both require one piece of info when traveling, but a single timezone wins out when synchronising.