By Randy Mitchell   The place: Prehistoric Los Angeles   The event: The very first marketing meeting   A small group of Paleoindians is gathered around a rock. They are locked in a heated debate over a timeless marketing question: “What should our tagline be?”   The meeting drags on and on. It’s an epic decision and consensus seems eons away.   Before they realize it, the meeting’s momentum begins to fossilize. Literally. Our intrepid marketing ancestors have been entirely engulfed by thick, black goo.   I cannot confirm that this actually happened in ancient La Brea. However, I have empirical evidence to prove that the tagline tar pit is real.   Agencies and clients frequently disappear into the primordial ooze of trying to