And of this Fourth Concerto for Orchestra Bayan Northcott exclaimed "but it's your symphony no. 2!"  He's right, in a sense:  the distant background model here is the Kullervo Symphony of Sibelius, which portrays the hero and the grim mythological terrain, tells his deeds good and ill, marks his passing.  My myth / saga / terrain is Piers Plowman and the allegorical world through which the larger-than-life figure ploughs his way — Vanity Fair Field Full of Folk with its deadly Sins under the iron / satin gauntlet of Lady Mede;  the Plowman's mighty ploughing;  regeneration, with Cardinal Virtues and Graces leading the dance;  Piers' apotheosis and disappearance when his task is achieved.  A Vision of Albion. 

Tilson Thomas's original generosity remained in mind: I'd already begun to project and sketch, when "half a concert" was whittled down to "half-an-hour".  In rehearsal at San Francisco the thing clocked in at an hour and a half.  Something had to go.  Fortunately, it being in six discrete movements, cutting was simple, if painful: "in San Francisco we loose our virtues", he winningly announced before each of the three performances, then turning to hold the capacity audiences enthralled by his powers of story-telling through a score still over sixty minutes in length, without a scintilla of restiveness or lapsing concentration.