A thought that came to me: What if Vulcan History had been revised and it was the Disciples of Surak that fled Romulus and colonized Vulcan?
It would make sense as Romulus has a more diverse ecosystem and seems to have a bigger population than Vulcan. Maybe it is a secret that only a few if any clan leaders and probably Archer know and hasn't been revealed as it could only destabilize the relationships between the Vulcan people, the Federation and the Romulans.
Maybe Spock knew it, too and it was one of his reasons to go to Romulus and found his reunification movement.
It would make sense as Romulus has a more diverse ecosystem and seems to have a bigger population than Vulcan. Maybe it is a secret that only a few if any clan leaders and probably Archer know and hasn't been revealed as it could only destabilize the relationships between the Vulcan people, the Federation and the Romulans.
Maybe Spock knew it, too and it was one of his reasons to go to Romulus and found his reunification movement.