No coach (no winning coach, at any rate!) ever said to his quarterback, "Tell the guys that when the play starts, they can just run wherever they want. Maybe they'll get lucky and things will turn out okay". Nor does an effective author toss out a bunch of details and leave the reader to try to figure out the connection between them and the main idea. Just as a coach chooses the best formation for a successful play, an author chooses the most logical writing pattern to present his or her main idea.
Think of the author of the paragraph as similar to the coach of a team. An effective author has a plan in mind for getting his point across to the readers, just as an effective coach has a particular plan in mind for executing a play. Once the coach decides on the play, he has his players line up in the proper formation to carry it out. The author does something similar: he organizes the details (his "players") in a pattern that helps him achieve his goal of a clear, easy-to-comprehend paragraph. The coach uses his quarterback to let the players know how to line up; an author uses his main idea to help him choose an appropriate writing pattern. It is those writing patterns that are the focus of this chapter. (I've used "he" and "his" in this paragraph simply because most football coaches are men.)
Here's the analogy in the form of a chart:
a range of possible plays
a range of possible main ideas
a coach who decides which play to use
an author who decides on a specific main idea to be presented
a quarterback who announces or signals the coach's play to the team
a main idea sentence (stated or implied) that announces the author's most important point in a paragraph
the rest of the team, who help carry out the play
details that support the main idea (make it more understandable)
the formation the coach uses to line up the players so they can best carry out the play
a writing pattern (organizational pattern) the author uses to arrange the details in the most logical way
The next time you look at a paragraph, think of the connections between football and reading!