In my experience, my perception depends on my own purity, and I see the same in other people. In short, it depends on the level I am at at any given moment.
As described in this topic, the limitations of perception do not affect the quality of the work performed with a person by the Higher Beings. Some people feel it better, some worse, and some do not feel anything at all. This does not directly mean that the work is conducted with different power, but it is certainly conducted with exactly what needs to be worked on. And as was said, one can interfere with the work through thoughts based on limited perception, thinking that it is not being carried out or is being carried out poorly.
Perhaps, to understand the healing process, one must understand the exact cause of the illness, and this begins with your karma, way of thinking, lifestyle, and flexibility toward change. As I see it, one can simply look in the wrong direction while expecting certain results when, for example, the healing work has already been completed and concerned the head—an entrenched way of thinking that is the cause of the illness and the condition from which the illness stems. Without understanding this, however, one may think that nothing happened and that the treatment was ineffective, even though one may already have noticed new thoughts or a new way of thinking within oneself.
I think it is better not to think that the power is low. Otherwise, that might really happen. It is exactly as powerful as it should be. But in fact, this issue can also be worked through, and one can strengthen oneself so that it becomes possible to receive more, if it feels like too little.