Yea rly. Sure you can OC with stock. But how far will you get? You WILL ALWAYS get better overclocks with an aftermarket setup.
A Copper HS, with Heatpipes and Artic silver 5, with a High CFM Fan attached will allow higher OC's than Stock. You cannot sit there with a straight face and say otherwise.
what are you referring to? what does 3.0ghz have to do with anything???
and.. no, no you don't need anything better than stock hsf for overclocking... you could easily get a steady 2.6 with any c2d with stock hsf... and that IMO is very good
and STE who are you to judge... do you own a c2d??? i know i do... lol.. and have tried plenty enough with it, to know stock HSF is enough