Anyone who still considers Pierre Boulez to be a threat or a dangerous malcontent – where to put those obligatory mentions of torching opera houses and valueless tonal music? here will do – might be pleasantly surprised at the playlist served up by this box of Boulez’s complete recordings for Columbia Records. Berlioz, Mahler, Debussy, Stravinsky, Ravel, Bartók and Wagner are the dominant narrative. The occasional disc of music by Elliott Carter, Luciano Berio and Boulez himself oblige us to play plink-plonk; but even these apparently unwelcome brushes with the avant-garde get offset by a performance of Beethoven’s Fifth Symphony and discs of Handel Water and Fireworks Music.

And as he prepares to celebrate his 90th birthday in 2015, the most dangerous truth of all is revealed. Boulez was an insider all along, who, unlike his frenemy John Cage, has always viewed progress as an embedded part of, and never an alternative to, tradition. That said, admire Boulez as I do, as a Beethoven conductor, he ain’t no great shakes. A plodding, micro-managed Fifth Symphony plays the notes but utterly misses the music. His Handel, though, is rhythmically assertive and detailed. Makes you wish Boulez had recorded some Bach.

The main focus, of course, is on mid-20th century music – Boulez’s chilly take on Schoenberg’s Pierrot Lunaire still has the power to seriously weird you out; his Webern is concentrated and artfully contoured; his Varèse is compellingly detailed and unafraid to push the dials beyond the red. You admire the sheer gestural finesse Boulez can bring to music you would not necessarily associate with him – Dukas’ La Péri for instance – but his classic 1969 reading of his own Pli selon pli, his ‘76 version of Schoenberg’s Variations for Orchestra and his mesmeric ’67 Bartók Music for Strings, Percussion and Celeste showcase best his love of intelligent design: recklessly beautiful, contentment in spades