Nah. As an actor who's done some voice acting, I blame the director on this one. Ghosts are not unintelligent, or SHOULD not be unintelligent. Their ability to access information instantly should be taken into account. Yes, they're very...human, in certain ways. They can get sidetracked. They can forget stuff. They worry, and sometimes make bad decisions. They have distinct personalities and predilections. But why can't a ghost replicate a voiceprint or speech pattern? If the Terminator can do that in the 1980's, a ghost in the year seventy million whatever should have no issue. It would have been way funnier if Ghost had said all the stupid stuff IN DRIFTER's VOICE, instead of doing a bad impression of cowboy #6 from an old Roy Rodgers serial. Playing ghost for humor works, now and then, when it fits into the wry, slightly fatalistic model established in Destiny 1, like in the Shield Brothers mission ("I didn't think they would leave the core intact...oh.... Bombs. It's covered in bombs."). Having Nolan do a southern accent so badly that this Boston native was slightly offended on behalf of Texans was a bit much.