addressed the comments in https://codereview.appspot.com/11374043/#msg2

src/buildings/helper/buildings-helper.h

@@ -49,15 +49,18 @@ public:
   */
   static void Install (NodeContainer c);     // for any nodes
   /**
-  * Update the node in the simulation scenario MobilityBuildingInfo according 
-  * to the buildings created
+  * This method goes through the whole NodeList and, for each node in
+  * the list, calls BuildingsHelper::MakeConsistent() passing to it
+  * the MobilityModel of that node. 
   *
   */
   static void MakeMobilityModelConsistent ();
   /**
-  * Update the MobilityBuildingInfo according to the buildings created
+  * Make the given mobility model consistent, by determining whether
+  * its position falls inside any of the building in BuildingList, and
+  * updating accordingly the BuildingInfo aggregated with the MobilityModel.
   *
-  * \param bmm the mobility model of the node to be updated
+  * \param bmm the mobility model to be made consistent
   */
   static void MakeConsistent (Ptr<MobilityModel> bmm);
   

src/mobility/model/steady-state-random-waypoint-mobility-model.h

@@ -36,7 +36,10 @@ namespace ns3 {
  * speed, pause and position are uniformly distributed random variables. 
  * The difference is that the initial values of this parameters are not 
  * from uniform distribution but from stationary distribution of RWM model.
- * The implementation of this model is 2d-specific and with nonzero nodes speeds.
+ * The implementation of this model is 2D-specific and with nonzero nodes speeds.
+ * In the 3D ns-3 coordinate system, the momement occurs on the 
+ * \f$ z=\overline{Z} \f$ plane, where \f$ \overline{Z} \f$ is a constant which
+ * can be configured using the Z attribute. 
  *
  * Based on NS-2 implementation by Toilers Research Group -- Colorado
  *      School of Mines (http://toilers.mines.edu).