I don't think it is clear from Jack's quote of Harker because that is not consistant with what Jack said about Chaucer " 'mediating' astro-navigational theory for a popular audience". The quote from Harker only covers the collecting end but in Fakesong Harker seems to include the presentation - which is more like what Jack says Chaucer was doing.

I'm not going to read it again to check but the impression I came away from with Fakesong is that mediation comes up over and over again because a main theme is collecting from the 'prolitariat' and presenting to 'bourgoisie' - the whole process. The mediation is where the faking comes in no "may well have" in the "siginificantly determined."

Which reduces the usefulness of the term and leads people to regarding it as prejudicial or a "threat". And leads to a discussion about something that should be clearer.