As in so many of these matters I am guided by The Spinners, who (on the recording I have, at least), sing 'Salford Wind'. The story I heard was that Salford City Council, mindful of the City's image, objected to this supposed 'slur' and MacColl changed it to 'smoky wind' which is what he himself sings on the semi-jazz version I have on his 'greatest hits' CD,
Sorry if this has been mentioned before in this thread.