Yeah I agree with all of those R2 descriptors (except the dummy turn one, dont you hold R1 with no direction to allow the ball to pass through your player untouched?) there Jimmy and sometimes it is noticeable but sometimes I dont think there is much difference with the shooting or the passing really. I experimented with it a few times and sometimes it worked and was noticeable but sometimes it didnt. Which pretty much sums up PES 2012's control system for me. It's party because of the lack of proper animations but I also failed to notice any difference on the power or placement of passing and shooting quite often. I cant count the amount of times I looked down at my hands and thought "I definitely WAS pressing R2 there!"
All of the others work every time with no problems, I should have specified I meant only the passing and the shooting because R2 definitely is one of the most important buttons in the game and works well in some situations. It's just inconsistent for me when it comes to passing and shooting.
That is actually a different one. Holding R1 will make your player lift his leg to dummy the oncoming pass. The R2 Dummy is different altogether PJ, if you hold R2 as the ball is coming towards you, then as the ball is just about to make contact, keep holding R2 and push the stick/pad in the direction you wish the ball to travel, the player will ignore the ball and turn so that the pace of the ball remains true and you can move off with the ball in the direction the ball is moving. It basically takes out the need to take a touch and turn. And unlike the R1 Dummy, which you basically pull off for the player to behind to benefit from, as that Dummy leaves the 'dummying' player static and flat-footed. The R2 Dummy means you can turn and move off without the pace of the ball being effected, or without being left static and flat-footed.
I did have a video on my phone of the above, and a goal scored by Tamudo where he used this perfectly, but I cant seem to find it. I'll keep looking, or record another instance. This was the first time I'd scored off the back off this move as well. But as you'll see, it is a totally different to anything else.
Also, holding R2 when you shoot or pass (except the X R2 pass) doesn't do anything as far as I'm aware. It only works if you press R2 once the power bar is filled, to whatever level.
I honestly don't know what I'd do without the R2 shot, nearly all my goals are scored with that, as generally, as you would expect, I get a lot more consistency and accuracy using this controlled system. As opposed to just getting his head down and smashing it.
Edit -
(Bugger !! I must have deleted that goal when I was clearing space on my phone. I certainly didn't want to, as I hadnt posted it yet, I can only assume it was part of some Highlights rather than an individual recording, as those are what I deleted.

Never mind, I'll just capture the Dummy again. )
Edit 2-
This has nothing to do with anything to be honest, but as I was scouring my phone for the umpteenth time, hoping that Tamudo goal was somehow still there, I found this one. This is just a great example of how to turn a defender inside-out, twice

You know how much defenders hate getting done once, it kills them to get done twice. This was Shot-Fake/Drop of the shoulder turn, and Inside R2 turn, (hold R2 and push direction, keeps the ball close) then a lovely R2 placed shot into the bottom bag. I love how he is sets off on his celebration run before the ball even hits the net. He just knows, yet he still checks his run ever so slightly before moving off again. Classic.
YouTube - Fake Shot Turn-R2 Inside Turn-R2 Shot
Edit 3 - Fixed the R1 error.