Bitcointalk staff May quietly banned multiple accounts anytime due to some people who use to buy and sell their BitcoinTalk accounts. I think its possible that you may face some problem for same ip. So you have to conscious about this matter & you shouldn't use Forum same IP
and a lot more carefull if you are going to make bounties, bounty manager don't like double account. and i know that a topic exist to list them in order to the mod to ban them.
but don't know if they do it...