In a complex modeling session, Boolean operations, combined with Mirror and Pattern operations, can make your work much easier. Furthermore, you can separate as long as possible the solids that you will later combine as needed to form the final object.
Let's see a few examples:
Example 1
It is not unusual that different models, although complex, contain common elements. Combining the Mirror function with Boolean operations can make you save a lot of time when developing a model.
Example 2
Create helix-like shapes (screws, springs, etc.).
Example 3
In a complex modeling session you can separate solids which, combined with Pattern and Boolean operations, will generate the final object. This allows you to deal with simple objects rather than with more complex and less manageable single objects.
To make the most of the techniques described above, you should be familiar with the Smart Pattern and Smart Objects functions.