Christoph Gedschold had his North American conducting debut on Wednesday with the Orchestre Symphonique de Montréal. It was mixed. A brave and slightly insane program contrasted two mobile pieces — Zosha Di Castri’s Lineage and Ravel’s G major Piano Concerto, played by Alain Lefèvre — with Shostakovich’s strident 11th Symphony,
which emerged as an hour-long hammering on a single theme.