So does G. Richard Shell in Bargaining for Advantage: Negotiation Strategies for Reasonable People. Shell, a Wharton professor, cites a study where half of negotiators committed to a goal in writing and the other half did not. Those who wrote down their goals were far more likely to win at the negotiation table. I picked up the book last week after several people here recommended it and am enjoying the many examples from famous people with which Shell peppers his lessons. http://www.amazon.com/dp/0143036971