There is a big reason that Vaughn's TN Brigade was sent to Mississippi to fight. They were mostly conscripts and from the most heavily Unionist part of Tennessee, so it was felt that if they got them far away from home, they would be less likely to desert. This brigade got hammered in the Battle of Big Black River before the Vicksburg Siege.
I second the suggestion regarding the new book on this brigade by the way - very well done.
Greg Biggs