Since I am NOT a total bridezilla,

I let my groom pick out his own tux for him and the guys. I just gave him the colors the bridesmaids are going to wear. He went and picked out a gorgeous charcoal grey tux and matching charcoal vest at mens wearhouse. The guys are going to have navy blue pocket squares (girls are wearing navy) and my groom is going to have a navy blue and white pocket square. It looks great! But he decided on a black tie. Is it just me or is the tie supposed to match the pocket square? or the vest? or one of the wedding colors? I casually asked if he had thought about having a navy blue tie instead and he looked at me like I was crazy! he said "what, are we going to the prom?" so now I need my knotties to settle this. Blue or black?
Thanks for the help!