Moser's recent recording of the concerto was no preparation for his fearlessly manic intensity on Thursday. He maintained much control, to judge from his smartly varied vibrato, but tossed aside typical coloristic effects for the most visceral expression possible. Nézet-Séguin urged him on and, during bows, showed his gratitude by going down on bended knee.
However questionable Richard Strauss' political sympathies, his 1945 Metamorphosen for 23 solo strings, finished when he was 81, is such a personal reaction to the cultural destruction of Germany - with devastation so deep and a manner of expression so distilled - that I'd much sooner hear this than any of the composer's snappier tone poems.
Nothing can equal some of the late-1940s recordings by musicians who had seen what the music portrays. In Nézet-Séguin's performance, every string entrance was clearly delineated, and every shift in texture was given full expressive significance. So instead of being a sea of string color, Metamorphosen was meticulously terraced, clarifying the piece's metamorphosis as few performances do.
Nézet-Séguin has had his ups and downs with Beethoven's Symphony No. 3 ("Eroica"), though Thursday's performance was an "up." It had all the fleet insight of his Chamber Orchestra of Europe outing 17 months ago, but with Philadelphia muscle.
Much of Beethoven's first-movement orchestration has black-and-white severity, which Nézet-Séguin heeded, but with dramatically placed dabs of intense color. The funeral-march movement was as cogent as it was grief-stricken. The final movement came off as a non-vocal version of the Symphony No. 9's choral finale - full of incongruities and odd compartments that other conductors skate over, plus tuneful elements morphing into greater nobility.
Additional performances: 8 p.m. Saturday and 2 p.m. Sunday at the Kimmel Center's Verizon Hall. Information: 215-893-1999 or www.philorch.org.