You're missing my point.. I'm not saying playing this game doesn't involve levels of multitasking. I just believe the article was intended for real-world job applications where the extreme differences of brain thought for different tasks one may encounter while multi-tasking is FAR more varied and requires much more mental re-focusing than managing 5 characters in the same game. It's the difficulty of trying to focus on one subject that the article is talking about.. and I just don't think that applies at all as much in WoW compared to the many difficult careers in the real world.

Flipping burgers, pulling fries, and taking orders = multi-tasking like WoW 5-boxing.
Writing code, dealing with employee interactions, handling customer negotiations, and balancing company finances = multi-tasking like the article was intended.

Hell, for the sake of comparison.. walking and chewing gum at the same time is multi-tasking, so why not include that in the article's argument for brain atrophy?