And the way I understand it is you short pins 5 and 6, so Clock is the same as input. This would basicly write the clock in the bios which probably kills it and the backup bios kicks in.
The method in the 1st post there (pins 4 and 7) will probably only work with some kind of button because you have to "hold" the main bios while booting and either hold during the flash or release right after boot. Not sure how steady your hands are, but I couldnt do that Shorting 5 and 6 looks more promising even though its a bit brutal.