Why do Commercial Study Guides Exist?/Why is Law Taught via the Case Method?

Until recently, I've been mystified by the vast number of commercial study guides available for law school. I think my initial attitude was something like: If you can't extract a rule from a case, you'd might as well save your money and shoot yourself now.

Conversely, at times I've been mystified by the case method: Why teach law this way when it's clearly not the fastest way to learn doctrine?

Now it all makes sense...

Law is taught by the case method because:

• Otherwise, it would be brain-searingly dull. The "stories" in the case books are the only thing that's kept me going some weeks.
• What you learn via the case method is not doctrine, but legal reasoning and reading.

Commercial study guides exist because:

• The legal reasoning and reading taught via the case method is hard. The more comprehensive study guides (like the Examples & Explanations* series) often explain things very much as the prof did in class, so they give you a second chance to make it stick.
• The commercial outlines pull together all the doctrine in an organized (sometimes even systematic) fashion. You could do this from the cases, but:
  1. It would take a long time.
  2. Much of that time would be spent on essentially clerical tasks, and who needs that?
  3. You may have missed some of the doctrine in class while the reasoning methodology was melting your tiny little brain.

To perform well on finals, you have to both know the doctrine and apply it in a lawyerly way.** Therefore, if you just rely on the cases from class and don't either extract the doctrine yourself OR use a study guide to do so, you'll be screwed. Likewise if you just learn from a commercial outline and didn't get the reasoning of the cases.

*Pedantic point: These should really be called Explanations & Examples, because FIRST they explain, then they give you examples.
**Or so I've been told.