DisableMPPAutoApply is the revit.ini setting which essentially stops Revit from automatically applying changes from Properties Palette based on cursor movement.

Interesting, Aaron’s tweet below shows that now you can move cursor at will, and a click in the drawing canvas will “Apply” properties changes.  Do we need to make a T-shirt for AU?

DisableMPPAutoApply=1

Enables or disables the ability to save changes to the Properties palette by moving the cursor out of the palette without clicking Apply.
Type = integer
Valid values: 0 = no (default), 1 = yes

from
http://help.autodesk.com/cloudhelp/2014/ENU/Revit/files/GUID-30C62836-F3F1-4B78-B1AF-DB4E3FD79FDF.htm