I like jeffdengr's iceberg analogy.
If you consider that people are creating many of their blockages, then going into the emptiness is actively contributing to the healing.
Also if they are in the emptiness they will be more receptive to the messages you are sending to them.
My concern is that unless you are quite advanced, or you are both skilled with qigong then working together might not be in harmony. The worst would likely be as if you weren't helping. The best would be as if you've doubled your effectiveness. If would take someone with more skill that I have to be sure that it is all in harmony. Of course, others may come out and say the everything is good. I've never heard of Master Lin describe a session where the one receiving is active. He will have people do meditations to help themselves but on their own, after the session.
If two qigong systems are different I could see the nulling out effect happening.
If the recipient is not knowledgeable, then I could see the healer being distracted by being too much in their conscious mind while giving directions.
Then, their is the advice of follow your intuitive instructions. Is it something you know is right or something you think is right?
Sorry for fence sitting again. However, my advice is to have the recipient go into the emptiness as Master Lin instructs. Many blockages disappear just be doing this.
You are perfection.
Iam2 
