It would be easy to circumvent, but I'm guessing the majority of meta-gamers would simply not spend the time to do so. They would make their own game and others would come to them or enter a game without restrictions. Multi-accounters are a different issue, but I wonder if the work to create a new account, or taking the time to enter a game where a few of those accounts are blocked would again deter much of it. Also, if a multi-accounter tried to use a secondary account to control a country in CD, not knowing which account would work (if any) might deter them from joining a game they knew had restrictions (I think these restrictions should be hidden until the attempt to log-in is actually denied).
Regrettably, it doesn't seem that anybody knows how much of a problem multi-accounting is. Are there sevaral persons with a lot of accounts or many persons with two accounts? What percentage of all accounts are not the primary (or original) pseudonym.
The easiest to know would be an anonymous online survey, but Kestas, et. al. would have to create it.
Finally, such a restriction list would make me feel more in control over my own gaming experience. Whether it actually has the intended effect may be subsidiary to my gaming experience.
Finally, there are pseudonyms I don't want to play with, regardless of whether they are honest gamers or not.