It might be, but it may only work for accounts set up in the database after the script was created unless someone manually went through and linked them. TBH it might not be a bad idea to nuke the unused double accounts and add something such as what you are saying, and only issue changenames from now on to prevent filling the database, which is how SA:MP, IV:MP, and partially MTA:VC work. Not sure about MTA:SA, but I'm assuming that if it has been developed, it probably works that way as well.