What I implied was that if people want emails of the other people, it'd be easy to gather them to one place, if no one fears spam.
Of course, any methods as such are allowed.
Actually, there are 8 VPs besides the capitals scattered around the map, and you need 8 to win, so you roughly need 4 capitals and 4 VPs or any combination thereof. At least if I understood it correctly myself.
So if anyone has the majority of the map(or uses cunning like long range summons if the VPs are defenceless) he'll likely have enough VPs to win. So it's a good plan to guard those VPs in case someone uses stealthy units or such to surprise attack and take them.