You don't seem like a smart allec; you seem like a disputatious know it all trying to intellectually bully people because you took an anatomy class. The OP had a simple question- do pullovers belong in a chest routine or a back routine? Almost every exercise involves secondary muscles as synergists. Pullovers do not significantly develop the pecs, but provide a good option in a back routine. The fact that you don't believe there is such thing as a chest exercise (I don't even know what that means) is immaterial to the OP's question.