That sounds like a nice thing to say; but in reality, if I were the one who had something to say that could be of benefit to the other person - than, no, I don't think I should always follow that rule. Sometimes one person has more to say than the other, in which case we should listen (of course). When we're the ones who have more to say, then I think we should say it. I don't think there can be rules for normal, healthy, conversation.
I think the main thing is that we listen when someone needs us to listen, when they have one word to say or a thousand. :)