I have been regretting the lack of manual recordings over the past few months with the Olypics and The Women's U20 World Cup. As you say the times are not certain or are subject to change before the event. I have in fact been forced to schedule recording by the out-of-date or incorrect guide data. Then I forget to check whether it has changed and find that a change in the guide wipes out the previously recorded shows for that time or I have to assemble a list of the segments of the recorded events and order them by time. Very, very frustrating.
I had been intending on posting that I wanted to see the Gateway add a manual recording capability like the Shaw Motorola PVRs but hadn't got around to it until I saw your posting.
Gateway and 3 Portals, Samsung FP-T6374 TV, Panasonic DMR-E80, Denon AVR-3808, Sony CX777ES