If you are getting used to the 3D/2D behaviour of datum elements in Revit you may still not be very familiar with the Propagate Extents button.
When you apply an override to a grid in one view you can tell Revit to apply the same change in other similar views. When you select a grid for example, the button appears, click it and a dialog box will appear that offers you other views the change could be applied to.
Here's the result...
You can apply this override to several grid objects at one time for example. Very handy!!
Edited: AUGI member Tim Gibson asked a question about this feature today as a result of this post. When the 3D extents of a grid is beyond a crop boundary the Propagate Extents feature no longer works. As long as we keep the 3D extents within the crop boundary it will work.