Hi Daniel,
I think there should be common rules for all WG and specific rules to each WG who needs it. Some WG could be OK with the common rules while another WG could need specific ones due to their work.
We tried to come up with common rules and couldn't find anything that worked for all working groups. Therefore we decided to let each working group make their own rules. Remember that there is no central authority. In the end it are the participants in the working groups that decide how they want to work together. As chairs collective we just try to coordinate and do what's best for our working groups. (I hope this also answers Nick's question) Let's see how this goes and then we can look at unifying/merging/etc those rules after we have some real experience. Cheers, Sander