Bike Anti-Porn - When Things Go Wrong

Or just put it in a chain tool and give it 1/8th of a turn; much more controllable than jamming a screwdriver in there.

I just get the pin centred by eye then flexing the chain on the newly inserted pin (90deg to the way it should bend) Give it enough pressure and this seems to loosen the link up nicely. Dunno how it works but it's a technique passed down the generations of my old club.