The other mods can correct me if I'm wrong, but no. There have been no community enforced/encouraged guidelines on intermingling and the community was, in fact, rather cliquey for a good while. We have speculated that it's only recently the groups became more cohesive as people with similar jobs (hunters, gathers, cooks, medics, etc.) began to define themselves more by their role than by which of the two groups they originally came in with.