he doesnt understand superman in kill bill he has bill give a long monologue about the nature of superman and how superman is the true self and clark kent is just how superman sees the world which is why clark is so mild mannered and weak
but the thing is that isnt true at all and is clearly tarantino speaking through bill clark was raised on earth. clark kent is who he really is. superman is what he think the ideal hero is so superman is the act and clark is the genuine person