My buddy has been trying backrolls for a while now. I've told him everything I can and I think its just up to him now to land it but maybe you guys could give him some suggestions..
here is a clip of a backroll he tried just the other day..
http://photos.wakeboarder.com/showphoto.php?photo=4156&password=&sort=7&thecat=3 107 any pointers?