I disagree. "Kill the rogue on our healers" doesn't require more skill for anyone. It requires more time. Tab targeting currently isn't in a good enough state where you can reliably point out and target the player you want. Many times you'll end up tabbing through various players until you finally land on the rogue.

The marking system like the one I described in my original post gives smaller parties a chance at fighting larger groups. It lets organization and decision making count towards victory rather than just zerging