The P3 Series of templates always have a:
Please note that the feature area will only show if a user places content in it and the feature area does not have to span the entire top of the layout.
These templates each contain a header, footer, feature content (F), main content (c1), secondary content (c2) and addtional content (c3). They are identical except for the ID on the body tag (f3a, f3b). These ID's allow them to be targeted independently with CSS.
When user enters feature content.

When user does not enter feature content.

These are identical to template F3a except the order of the main content (c10 and the secondary content (c2) has been switched. Also the IDs on the body tags are different (F3c, F3d)
When user enters feature content.

When user does not enter feature content.

You can use templates from different series in combination to build sites. For instance, if you need template F1a for the home page and F2d for the interiors then go for it.
See how one page template can present multiple looks through the disappearing act of the magical feature.