The problem with only discovering where you might reverse a technique or apply an atemi "in your mind" is twofold. On the one hand, your mind may be wrong. I've been in techniques I thought I could reverse only to find out i couldn't. How do I know, because I tried and got shot down. On the flipside, if nage leaves gaping holes in his techniques but nobody walks through them, he never learns to close the holes.
Strong attacks and counters aren't necessarily about ego, but about martial training and trying to give your opponent what he needs to learn, and maybe he needs to learn that his technique could be better. this also goes for attackers. In line with what George mentioned earlier, if your attacker is "jamming" in a way that is martially useless, their are lots of fun ways to point that out