The title of this piece alludes to 'Woodpecker and Lyre-Bird' by Vernon Watkins; the last four lines read:
 

Lost art's unsearchable span,
 The poem is shaped by belief:
  If the song is justly measured
   The dead may be heard to sing.

Lines that have a clear connexion with the last two lines of the same poet's 'The Childhood of Hölderlin':
 

Because his song was pure false tongues
   are silent.
Through him the dead speak, and the
   quick are changed.

And here is the contemporary Danish composer Vagn Holmboe on Tapa Haydn': 'Haydn's close connection with folk music … is due not so much to a direct adoption of tunes from the folk music by which he was surrounded, and knew so well - attractive songs and dances of Austrian, Hungarian, Croatian, Slovakian origin - but in far deeper measure to the fact that his music has its roots in folk music. No matter how complicated, subtle and refined his form and technique may become over the years, he always preserves the spontaneously human and straightforwardly musical utterance, which is fundamental to folk music.'

Just measure, the shaping of a poem by belief, purity of expression, 'the spontaneously human and straightforwardly musical (or poetical) utterance': these are not the accepted ways, in the 'best' - which is to say, the most influential - circles, of talking about music or poetry, ...