Below is a test of a single master calendar in one gmail account that has shared access to 3 additional individual calendars.
The individual calendars represent event offerings from various OM'ers. Each was created using a separate gmail account using its OWN local time zone as default time. This makes it easier for author to create accurate time events. (In this example, USA pacific, London UK, and New Zealand.) Each of these separate calendars is made public and shared to the master calendar.
This page displays the master consolidated calendar. The master calendar can have additional events of its own. Plus all the events from the "feeder" calendars show here too. Note that all times are automatically adjusted to fit the time zone of the master calendar. (In this example, India Standard Time.)
As you can see below, the user can pick any OTHER time zone to display all events. All times/dates will automatically adjust and display correctly for the selected time zone. This works even for events where the time difference causes it to move to the day before or after.
Pick your preferred time zone for event listings: