I doubt it requires it, or most people's would have burned up by now

I'd say it depends on what cooling you've got on there now. If you've got active cooling, or a good sized heatsink, I wouldn't worry about it. If you've got a small HS with no fan, then it wouldn't hurt.
The stock HS that came with my 8RDA+ was small and got very hot, especially when OCing via the FSB. I replaced it with a Vantec IceBurg and its nice and cool, so it depends on what you've got at the moment.