It would, but then he'd lose all his COD stuff and all of that.
Here's an exact explanation:
E-mail:
1. Go to Account Management.
2. Go to Account Information.
3. Go to Sign-In ID
4. Enter your password.
5. Change your email to whatever you like.
Password:
1. Go to Account Management.
2. Go to Account Information.
3. Enter your current password.
4. Enter the password you want and re-enter it to be sure.