6. It is a common misconception that we can copyright our code to "The MAME Team." But the MAME Team is an amorphous, ever-changing, and non-legal entity. Thus, copyrights on the code in MAME can only be held by individuals. Because of this fact, and because there is disagreement on how the code should be licensed, there is never any hope of ever untangling the licensing mess until the files that make up MAME are attributed. Attribution is an annoying and messy business which I hope can eventually be automated.
You can, if you define The MAME Team as an organisation with registered members.