line collections

I thought I would implement draw_line_collection() for Cairo and looked for
an example script I could use for testing. Yet after adding a
'print "line collection"' statement to backend_bases.draw_line_collection()
and running I did not see any examples using line collections.
Does this mean that line collections are not useful, or just that there is
no example script (called by which uses line collections?

Also, is it worthwhile implementing these collections routines or are they
effectively deprecated and about to be superseded by new path based drawing