Metal Gear Solid 2: Sons of Liberty HD Edition Tips

O2 Test
When Solidus attempts to suffocate you with his "arm extensions" on top of the arsenal gear you are supposed to press a certain button repeatedly in order to survive (triangle button in my game). While in difficulties from easy-hard this isn't impossible, many people isn't able to pass this test on extreme and european extreme, and not everyone who can't pass the "test" can go and buy a an auto-fire controller.
So there is a trick that makes your O2 gauge drop slower (this doesn't mean that you have to stop mashing the button when he suffocates you). Now when the cut-scene on top of the Arsenal Gear begins, you can't move, but you can "turn your head" so move to the left; you'll see Snake and Fortune there. When Solidus stops talking and starts to suffocate you quickly start pressing the button but at the same time turn your head to the left again, but now you can turn "more" to the left, up to a point where you will be able to see Ocelot, keep the analog stick to the left to keep watching Ocelot while you mash the button. Believe it or not now your O2 gauge will drop slower, I know it doesn't make any sense why this happens, but it is true. It was thanks to this I was able to survive in both extreme and european extreme.