Small group/unit cohesion and bonding that starts with a boot camp platoon should be disrupted by totaling reasigning everyone, completely mixing them up about half ways through and then again in infantry training. Granted, bonding is critical but small group bonding is familial in nature, maternal, and family roles can assume at times importance and status almost equal to the mandates of command and control, doctrine and discipline. You are putting people into an alien environment and they form family roles, very subtle things to understand, and I am only suggesting that C&C, D&D, which is paternal, has to intially take absolute precedent over the hearts and minds of the green weenies. Once they get into the real life of the military and direct application, they will bond with their brothers. 7 is a magic number when it comes to crew size IMO.