However after seeing that scene it appears that McDiarmid was asleep or on heavy doses of pain killers when he recorded that scene.
Also that the make-up crew, probably unuccustomed to ACTUALLY having to do latex work after years of being shunted aside in favour of the CGI crews, have completely forgotten how to do their jobs.
Gee, I don't know why GL just didn't use a CGI Emperor considering that he has stated that he hated the limitations of Latex and puppets and that CG 'just seems more real' to him.
Give me the Clive Monkey-Woman Reville Emperor over this stilted crap any day. It's amazing but the Reville-voiced composite actually does a more convincing job than McDiarmid. That's not really fair I guess as McDiarmind did a fantastic job matching the OOT TESB Reville-monkey-woman with his wonderful performance in ROTJ.
This is just further proof of how much Lucas sucks and how poory executed, not to mention totally unnecessary, all these arbitrary changes to our beloved saga are.