However, it was basically a feint where you swapped attack modes in the middle of a melee attack and it would like a feint, but as soon as you swapped back to melee, it would continue your attack, so basically it was a feint without actually prolonging your attack. I explained it more in depth to Vince, but am too lazy to type it all out again. My video showed just the basis of it, however I did not have anyone at the time to use it against, and I am not exactly sure how to do it perfectly everytime, so the video had some flaws, but I managed to pull it off three times, once in beginning, once in center, and once at end. I'm not good at it because I never use it, so my feint wasn't entirely obvious, but many people do it much better and would be able to show you better, my video was just a visual example for Vince.
http://www.twitch.tv/death_by_emp/c/2679138Edit: Just seen Fallout's post, replying now.
Oh, and I believe the way it was patched was by adding a delay to weapon mode swap.
Before any of you complain about me poorly doing it in the video, Vince was aware I was not very familiar of how to do it, however I was not the only person informing him of it, many EU players also gave him examples.