Bingowings said:
Tarkin could still say, "Terminate her, immediately!" and Vader could say something like, "No I will deal with her myself".
That way he sounds in charge of the situation and not Tarkin's to order about.
It does make Vader sound a bit like a scratched record though as he practically takes the same line with Obi-Wan.
Threepio translates Artoo's discovery that the Princess is scheduled to be terminated.......?
J