I don't know if I'd quite agree with you on HOW different the game is with/without the patch (or on the specific differences) but I'm still baffled by people who reckon there were no gameplay changes at all and it's simply placebo. I think the changes are a little more subtle than you suggest, but to not see them at all strikes me as bizarre.
I think the game is near on identical in every way possible, with the exception of the CPU. Even then, the CPU has had some very minor, minor tweaks but they are ones that have had too much of an impact on how the CPU behaves. I think Konami looked at the game out of the box and decided (wrongly, in my opinion) that tackling was too effective. So they toned that down, and made the CPU just that slightly bit more aggressive. Combine the two, particularly if you're playing on Superstar with the ML default players, and you get an ultra-brutal CPU that skips past your challenges far too often because it calculates that that's potentially the best rout to goal. Pre-patch, in my experience, the CPU is tackled a lot more or is fouled more, meaning that to keep an attack going it looks for a pass rather than a dribble. I think this is just a side-effect of the tackling being toned down rather than new, coded behaviour. Sometimes tiny tweaks can upset a whole load of other things.
The patched version has the facility to become extremely direct in the passing and dribbling, which in turn makes it more like PES2012 in that respect. I think this difference is more than possible just by tweaking some parameters in the game's code and I think it's had more of an effect than they'd have expected. I wouldn't be surprised to see this reigned back in whenever they inevitably patch the game again.
But, I will say that most people will disagree with this because it's nowhere near as apparent playing with better teams. Play a ML with the default players and you'll noticed the difference.
This is something that's bugging me at the moment in my ML - the fact that every single team in the league except me has scored fewer goals than the number of games they've played. I'm second in the league, but I've scored more than twice as many times as the teams above and below me. It's farcical.
Also, you mentioned the other day about the buggy Teamwork stat in ML... I checked and you're quite right. Perhaps that explains why my youth team CB, who I've been playing all season and who has already gone up to 83 OVR, seems to behave so oddly at times when AI-controlled, despite his gifts as a defender. His teamwork stat is still on 53.
Then again, I'm still not convinced it really matters much in the wacky world of ML. I just signed a striker in the January window, he's obviously got a similarly dreadful Teamwork stat, but he's making great runs and linking up really well with the rest of my forward line - absolutely no suggestion of low teamwork there. I reckon PES 2013 (which I'm still enjoying, despite everything) just does what it wants to do at least 50% of the time, and all these numbers and sliders and settings are mostly decoration.
I'm really confused by the teamwork thing. In my first attempt at ML on Superstar, with the patch installed, I thought teamwork was the most vital stat in the game. I thought that my players weren't functioning properly, especially in defence (and yeah I found the exact same thing as you with Nouhei) because their teamwork stats were so low. Those stats only increased after a full season, and only by a point or so.
However, my ML so far on the same settings without the patch, is so different. My players still have the same low teamwork stats but it's not really making any difference.
I've just signed a Brazilian striker called Everton, and his teamwork instantly dropped from 73 before I signed him, down to 45 once he signed for my team. On the patched version on Superstar, he would have done really odd stuff like running past the ball, moving away from it when he should have pounced on a loose ball in the penalty area etc. Yet on the same settings, just without the patch, he's been my star player, scoring 5 in 5, and some of those have been pretty spectacular. His link up play has also been great.
Hopefully this means that teamwork plays a part but not as big a part as in the game post-patch. I dunno what it is, maybe it's just a side effect of Konami tweaking certain parameters and it's screwing with player's teamwork abilities more than it should. Either way, the game without the patch, with crappy players is still extremely tough, but I've at least managed to set up my tactics to win three of my first five games by winning 'ugly'. I'm talking holding out for wins by heroically blocking shots in the six yard box (Nouhei in particular is rock solid now), whereas before I deleted the patch, they'd just slice through your defence and hammer perfect goals in every time.
In fact against the same side, on the same difficulty, post-patch, I was 5-0 down in 28 minutes. The CPU played like a hyped up robot. Without the patch, against the same team, same settings, I had less of the ball than the CPU, managed a goal from a rare counter attack, then managed to park the bus until full time by blocking and tackling pretty desperately at times. But unlike the post-patch version, far more of my standing tackles actually worked. And those that didn't, resulted in fouls and yellow cards which again is more realistic.
But without having the cushion of being able to waltz past tackles like it does post-patch, the CPU actually has to play the ball around you and it makes for a more realistic game. And all because, in my opinion, Konami changed a couple of parameters with tackling and CPU accuracy in a 12MB patch.
