I can't say why some people can't see a difference. That's strange, but for my own experience, I just tried 1.03 and saw a big difference.
First of all, referees blowing whistles at a higher rate, and that's good enough.
Then, the gameplay. I'm not sure if it's slower, I'd have to play more games. But what I noticed is the AI's behaviour, the way they react in defense.
I explain : before, when I was attacking but then losing the ball in defense, the CPU simply and impossibly ping-ponged their way out of danger. Now, for 3 games in a row they never did it. It reminded me of the old WEs. One of the defender held the ball, tried to run to free spaces and find someone available. That was crazy. I noticed that if there's no empty space to run to, he will clear the ball with a long kick.
In midfield, they rarely ping-pong, I see a lot of players holding the ball and trying to pass it calmly, and sometimes missing the pass, giving it to my players. A ping-pong was never missed before, it was impossible to intercept a pass, or almost impossible. Differences felt obvious, the CPU simply plays in a different way. They also try more low trough balls when close to my pk box. I really see more holding, more intelligent passes and more miss-passes from the cpu. It's great so far. And if they still ping-pong a bit, just a bit as it is now, it's fine for me, as it's the same in real life football. It's nice to see and it's challenging.. but it has to be done a very few times, between good passers, not all the freakin game long as it was. And that's what I noticed now.
Oh, and the way I experienced the differences is by playing the same saved final uefa game I play at least 10 times for various reasons. This final used to be almost the same everytime I played it. Today was totally different than other times.