That was a problem with the direction, not the casting.
+1.
Seriously, I can't see how the casting can be blamed over the directing and writing. To be fair, most of the actors in the Original Trilogy weren't going to be contending for any major acting awards and some of them were downright goofy and wooden, but the writing and directing by Lucas, Kershner and Marquand overcame most of the performance limitations of those people.
Portman. McGregor. McDiarmid. Jackson. Christopher Lee. That's the kind of cast most sci-fi and fantasy films wish they could assemble for a sequel or a prequel. They were fine. Even Hayden Christensen was competent enough, but they just weren't given the best material nor the most skilled on-set direction much of the time.
+1 again.
Darth Vapid, anyone?
