Each FeedTools::FeedItem checks to see if the feed can be redistributed (lines 2039-2051). This check only needs to
be made once per feed, not once per item, so it should be a method in FeedTools:Feed. Moreover, it should be possible
to switch it off in cases where the feed is known a priori to be redistributable. In my case, I am programatically generating
a feed of changes to an internal data source, so the redistribution check is expensively redundant.