If one of your accounts gets banned, they will all get banned if discovered. On Bitcointalk, they don't ban the account, they ban the person behind the account making the posts. So if you get banned and you come back to start over, that new account of yours will also get banned once a connection has been proven. It's called ban evasion and is against the rules. If you get banned, all you an do is create an alt account to appeal the ban.