Is there any significance to the fact that David and his men were marching at the rear?
1 Samuel 29:2 (ESV)
2As the lords of the Philistines were passing on by hundreds and by thousands, and David and his men were passing on in the rear with Achish,
It is very possible that David purposefully ensured that his men were placed at the back. This would be the perfect position from which to launch a surprise attack once the battle had begun.
2 As the lords of the Philistines were passing on by hundreds and by thousands, and David and his men were passing on in the rear with Achish,