Well, Premier is displaying the actual frame so I'm not sure on how we could deinterlace the preview without actually deinterlacing the video.
Perhaps you could change the monitor res to something less than 1920x1080. this will then force premiere to resample the footage removing the combing.
Perhaps you could change the monitor res to something less than 1920x1080. this will then force premiere to resample the footage removing the combing.