It's a must to master the art of using and creating scripts. Every good salesman knows this.....
However... we must remember that sales is the greatest sport in America and we can't use the same strategy with every team (client - potential prospect) that we play.
A master saleman can look into the eyes of a prospect and judge wether or not to use a script, 3 step close, identify his problem, let him realize his problem, present a 30 second close, or simply walk away. It can only be achieved through experience in the field face to face, on the internet or whatever.
The key is testing and developing your own style with the ability to adjust as needed. Isn't that what made MJ so great?