[whpalmer4]

The OmniFocus Reminders calendar is just a sneaky way to get notifications of impending due events on the iPhone/iPod touch/iPad in the absence of a reliable notification service that could be used by 3rd party applications under iOS 3.x. It puts in a zero-length appointment at the time the notification is to happen, and the calendar app does the rest.

My suggestion is that you not try to maintain these items in both places. If you want to make an agreement with yourself to answer email from 9 to 9:30 every morning, put it on your calendar, not in OmniFocus. You're not bucking GTD orthodoxy at all by doing so, any more than you would be by putting a trip to an office in another city to meet with colleagues. But when 9 am rolls around, you work on answering email. If you aren't going to stick to the agreement, there's little point having it in your calendar.