Pressing vs Concentrating

No, this is not the case at all. Acupuncture is generally not a "point to condition" type of therapy. By this I mean you cannot generally just press a couple points and have conditions treated. Proper treatment requires proper diagnosis and then using a selection of points which create changes in the person to facilitate their health. There are differences between acupressure and acupuncture and certainly from just focusing on the points. In very general terms you want the energy to go somewhere not just collect at a point - in purely technical terms this type of activity (i.e. focusing on a point, over pressing a point) could theoretically make a condition worse - or at best have limited change.

The benefit of acupuncture vs. acupressure is that you can stimulate many points at the same time which, if you follow the theories correctly, will create a stronger movement. Now there are some points which have very broad functions and are useful with acupressure for fairly basic conditions (headaches, morning sickness, etc.). To see these, you may want to read my article on common acupressure points and their usages.

Certainly within medical qi gong and other forms of energy healing you are using intent, to some degree, to move energy within the body - but it is far more involved than simply concentrating at a few points. Again, qi gong requires a strong understanding of the underlying theories of Chinese Medicine and a strong level of energetic sensitivity to get good results.