Some of the lines drawn lie outside of the boundary of the face being split. All lines used to split a face must be contained within the face being split and cannot intersect or overlap any of the boundaries of that face. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
Syntax
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