I am not sure about that exponential factor - I think the integrity of a community is a reflection of the overall integrity of the individual members; and that the community, not an individual, has the responsibility to determine its own profile.Greg
For smaller groups putting that responsibility in action is more likely to work. The smaller the group the better chance of it working.
The integrity of a community as large as the Aikido community cannot be measured by the overall integrity of the individual members because it is impossible to know all the members let alone their integrity. There is a perceived communal integrity based on who we have direct contact with or have heard about.
As for Marc's lament, I will go with Epictetus,
"Men are disturbed not by things, but by the view which they take of them."
and Dr.Fred Little,
"As I grow older and more careful regarding how I choose to spend my limited time, increasingly, my choice with such individuals is to ignore them and to avoid situations where it is necessary to interact with them."