Actually, I didn't explain that point well enough. If you read that whole section of the recipes book, it starts by saying that most people think that most people think it's not worth the effort, but then, ultimately, because Jasper won't compile pages for them, they just walk away. The very next section is about Velocity and how simple it is to test templates there.
Furthermore, their whole 'gold master' approach is super simplistic and not given much serious treatment.
Let me be super-specific. In JSF, the framework kicks back messages automatically if a validation or conversion fails. I made my own custom component to pick up those messages and turn the style of the corresponding field's label to red text. Wouldn't it be great to have a unit test that creates a form, forces an error and then checks to see that the style of the label in the response (the same page being redrawn) was red?
Most people think of unit tests as being simply so we can figure out if something works. Automation yields a much broader value: being able to know that something works at all times.