[web2py] clarification needed: response.files.append()

[lyn2py]

I am on 1.99.4 stable

I tried include some files with response.files.append()
  1. outside of layout.html and
  2. after {{include 'web2py_ajax.html'}} in layout.html,
but they didn't seem to appear in the html, for example:
{{response.files.append(URL('static','js/jquery.example.js'))}}

Is this expected? I haven't tried this before on previous versions.