Of course Peter Jackson's version of Lord of the Rings included perhaps the most successful CG motion capture character ever, ie: Gollum. I think motion capture is much more effective than makeup and costume, particularly when a character diverges from human parameters or when a face needs to move without the burden of heavy makeup for old age or whatnot. Even the orcs in Jackson's Lord of the Rings had CG enhanced faces.

Performance capture loose out more than 90% of what that is possible with CG. Art is about distilling -lifting out what that is important so people get the message and not get lost in insignifant details.

You'd think that by removing that 90% of the insignificant possibilities you would be left with what is important. In any case, people do go over the product of motion capture to add, subtract and tweak movements. I don't see any inherent superiority in the point-and-click key-framing of puppets powered by animators instead of actors, unless the character simply isn't human enough for motion capture to be practical.

By the way, do you know of any technique that doesn't use the real actor's voice?

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