There are many different theories about buildings in hot-arid climates but here are a couple solid references.
In the Ballast 5.0 study guide it says:
Thermal mass should be maximized, not minimized. (Helps retain the warmth from the day into the night, then retain the cool from the night into the day.)
Openings should be minimized to reduce heat infiltration.
All windows should be shaded.
A compact form is ideal for minimizing heat gain.
In the Ballast 5.0 review manual it says that "for hot-arid regions, squarer shapes are better. For external-load dominated buildings, the plan should include open courtyards; for internal-load dominated boilings, a solid, multistory arrangement works best." The diagrams show two options, one for external load dominated buildings in the form of a courtyard (these are typically houses and small buildings) and the second option is for internal load dominated buildings in the shape of a rectangle (these are typically larger buildings such as commercial and industrial).
However, in the Brightwood study guide the hot-arid climate section only discusses the use of a courtyard. The whole idea of using a courtyard in a hot-arid climate is so you can use evaporative cooling with a pond, fountain, or plantings to cool the rooms. Then the outer walls will only have smaller windows that are high up to allow the heated air from inside to escape.
So my conclusion is that courtyards in hot-arid climates are ideal.