Is it not possible to integrate two Google accounts? You can clearly add an Outlook and a Google account side-by-side, so multiple calendars must be fine, so why can’t I seem to add two Google accounts (personal and work)? If RescueTime can’t see my entire day, it pretty much defeats the purpose, no?
I agree that this is a much needed feature. Having to share a calendar to the sole Google account you are syncing with RT in order to see it in RT creates clutter in that Google Calendar. Much better would be to allow multiple Google accounts as you suggest.