I find the responses here really quite predictable. Those who are good at atemi or want to be good at atemi say that punches should be more than just a setup for a technique, they should be a technique in themselves. Those who are not good at it (or don't wan't to be), of course say otherwise.
Imagine having this debate in a karate forum: "Should punches be strong?". kinda funny isn't it?
In other martial arts there are also "fake" punches and kicks to set up other techniques. But the difference is that in training, force is put into the "fake" strikes - that's how you get good at it. Sure you can punch to the body then to the face, or whatever, but training is done to simulate the real thing (without actually hitting the other person).
What I was talking about was the "punch" up, "tap" with a block, then throw, etc.