A conversation is not just the act of transmitting information between two persons; it's a creative process, where new information is created. I would say that the percentage of "transmitted" information versus freshly created information is 1/10 or less. In fact, a conversation is more like an act of improvisation. When we start talking, we rarely know exactly where are we going. Of course, we may have a direction, some really important information to convey that acts as a "beacon" for us. But then, all the rest is pure rambling, digressing, random walk in the phase space of thinking.