If your entire party is hiding the enemies don't attempt to look for you, even as you and your squad are dishing out damage between rounds. I had a great time playing the last game but my friends and I refused to use any form of stealth in combat because how badly it breaks combat (and overall immersion), by giving you 100% guaranteed control over who enemies attack and in the worst case giving you a free round of damage. I would at least expect enemies to walk towards the source of damage. I'm really hoping this gets fixed because part of the fun of hiding and sneaking around is the ever present risk of being caught.