Thanks for starting this thread, as it's an interesting set of circumstances with George and Cindy as grandparents of the victim and parents of the alleged murderer.
In most cases someone who is a witness must stay out of the courtroom until after they testify. This motion appears to be requesting that they be allowed to be in the courtroom throughout the trial proceedings, from beginning to end.
If the state is going to present their case in any sort of chronological order, I would expect them to begin with the events of July 15, 2008, with George and Cindy picking up Casey's car at the impound yard, finding Casey and bringing her home, and Cindy's frantic call to 911 reporting Caylee missing. If this is the case, I would expect George and Cindy to be among the first witnesses called to testify.
We all know that George and Cindy will lie and say anything to try to make Casey's actions appear innocent.
I'm confident that LDB and JA will be able to elicit the testimony of the events of July 15, 2008 from George and Cindy, and will try to shut them down from going off on any long winded explanations.
After watching their testimony during the "agents of the state" hearing, George is the one I think will be the first to be barred from the courtroom. He's angry at the world and volatile. His testimony at that hearing was reminiscent of his testimony during the depositions taken by John Morgan and Keith Mitnik for the civil case.
Cindy's body language during the pretrial hearings, showing that she disagreed with the testimony presented by the state, with her facial expressions and drawing/writing on a legal pad, will not likely to be tolerated at the trial. This might get her barred from the courtroom.
I think it might be a good idea for the judge to allow George and Cindy in the courtroom. Let the rules be known and the first time either George and/or Cindy ignore those rules and overstep their bounds, bar them from the courtroom. Then the blame will be on their shoulders that they were ousted for breaking the rules.