I agree with you but my work is in government organization and there are more than 2000 users and several SPs running with this method. It's amazing since many tables should be change triggers by check constraints. Unhappily I no have a choice in this moment to do this (but I really will do an re-design in future). You see any trouble in apply this solution or I really try to fight to change my mind. SOS. I start in my job less than a month for SQL tuning in an institution where everyone has been done what want. Thanks again and if you have any other suggestion, please help me.
P.S. Sorry for my poor english.