Hi Feather,
That's what I was thinking might happen- the energy being experienced and amplified by a group. I was thinking of encouraging guests to put their hands on a part of their body that needs healing and to send healing energy. This teaches people about self-healing, even if they do not have attunements, and I think will encourage them to open up more.
Those new to Reiki are often closed or guarded in sessions and don't really know how to "open up" and receive the energy.
Fascinating stuff!