Yep, put them in a group and you'll do just fine!
We put out buoys so we could drop them together so they are all touching, this allows the fish to move through the entire area and use all the 4 inch "trunks" as shade or ambush points as the sun moves, or they can snuggle by the posts and branches for protection/security.
My favorite cover has a Big PVC Main "Trunk" and then smaller "Branches"....IMHO, this is the best cover you can make for ease of fishing off of!