Being geeks, we have a tendency to invent solutions that are theoretically wonderful but quite impractical. The current 3/5 rule avoids that and is fairly easy to check algorithmically. I think we need to keep that simplicity as much as possible. So something like the following might work. Either 3 out of the last 5 meetings or 3 out of the last 10 meetings and (RFC author or WG Chair or AD in the last 5 years) Brian