Re: HTML Time Zone proposal

Hi Addison,

Overall a nice improvement that addresses my concerns nicely.

 One new part isn't entirely clear to me now, however:

> When the tz attribute and the time zone offset in a time value disagree, the tz attribute overrides the offset for handling and display of the time value. For example:
> 
> <time dateTime="2014-04-30T12:10:11-07:00" tz="Europe/London">
> The above is interpreted or displayed by the user-agent using the time zone "Europe/London", even though the time value has an offset of GMT-7.
> 

Does this mean that London time zone completely overrides the offset, i.e., this would be interpreted as 12:10:11 London time? Or does it mean that the time with that offset would be displayed as the London equivalent to 12:10:11 US mountain time on that date (19:10:11 in London)? The text is ambiguous since it is not clear what “handling” means (at least to me). 

I would hope that it is the latter behavior, but it needs to be clear either way by explicitly stating what the user agent would/should show in this case. 

Best,

Arle