Considering the difference among different circles, which would be the most common role of them when managing the validation process?
I think local circles should meet physically the person or the group that presented the idea. Thanks to a previous listening activity on the territory, the local circle should be able to understand the context and the possible connection of the people who present the idea and the local community, The local circle can certainly give good feedback and put in contact the promoter of the idea with other people, in order to get feedback even from unknown people.
agree @urbanohumano. Local circles should carry out most of the work on the opening phase and just keep inform regularly the global circle
Agree with the above posts, I think keeping people informed is a very important task for local circles. Documenting how they are listening to the community, the insights they are gaining and any feedback they have on the methods, not just for the global circle, but for people within the local circle (who may not have been present in an activity) as well as the local community.