I'm not criticising FM, cause it is one of the best games ever, but the AI is much better at finishing.
You often see your team miss 6/7/8 clear cut chances, and then the AI take one. Of course this is realistic, but you rarely see it the other way around. Yes, you see your team win games against the run of play, but they opposition rarely miss multiple clear cut chances.
I wouldn't say human teams miss that many CCC in games. In fact, I rarely have more than 6 even when I have scored 7 or 8 goals. Unless you are referring to shots on target and not CCC. Your thread did make me go back and look at a few matches in my game though and I couldn't see a big difference between AI CCC and goals, and my CCC and goals.
My first leg cup game vs Zaragoza I had 6 shots, 5 on target and scored every single on of them, winning 5-0. I let Zaragoza have a number of shots at goal but in long range or narrow angled areas. I don't set my team up to create 30 shots and 7 CCC's I set my team up to create really good chances, some of which don't count as a CCC.