What are you trying to do? Are you just trying to display an image from a laptop or Tablet PC? Is the Tablet PC used often or is this for a one time guest? What does the computer that "controls the video system" actually do, is it simply a video and audio source or is it actually running production applications and controlling things?
You might be able to share desktops, but this could be a little cumbersome as far as who controls the sharing and getting the desired image, both in what is seen and in image quality. For example, can you get the image you are wanting to display to fill the Tablet PC desktop and then get that shared to fill the local PC desktop?
