In a press release about the opening of London's new Tate Modern museum
there is this:

   Sir Harrison Birtwistle's '17 Tate Riffs' complemented the awesome
   building - a renovated power station housing more than 600 works of
   art - quite magnificently.  After all the damp squibs, hangovers,
   and the anticlimax of the 'Millennial Experience', how uplifting it
   is to have a building devoted to 20th century arts on such an epic
   scale!

It's hard for me to imagine the word "riff" associated with anything
by Birtwhistle.  But apparently John Wallace and others trumpeted away.

Did anyone hear this? And if so, can you tell us what it was like?

Scott Morrison