ReportInvalidReferences has very big imperfection, it report by default all variables, properties and method which has null value.
This may cause many problems for developer.
I for example need only validate template without any data, only check which contain right variables, properties or method (which exist), it's value is not important for me.
I tried use my own ReferenceInsertionEventHandler for replace null value with "" (empty String) but Velocity call InvalidReference handler before ReferenceInsertionEventHandler.
I suggest configuration options for this (repor or doesn't report null value)