@rwinch It would certainly make more sense IMO. Particularly, if you can now configure **sourceFileName**, the meaning of *index.xml* is certainly diminished. By default I would NOT expect *index.xml* to be expanded, if **expandPlaceholders** is empty. 

But then the question is, how important is backwards-compatibility? Maybe a 3rd possibility would be to have expandable default to *index.xml* but fully honor **expandPlaceholders** if it is set (and we allow it to be empty) :

    def expandables = '**/index.xml'

    if (project.hasProperty('expandPlaceholders')) {
        expandables = ("${project.expandPlaceholders}").split(',')
    }

I think that should not break too much.