So, it seems that this new arrangement of M9 is apparently a re-orchestration. The questions are, to what degree, and would Mahler himself sanction it?
Wade
Mahler himself was a fan of re-orchestrations and arrangements, for instance Beethoven's and Schumann' symphonies, Schubert's S9, Beethoven's overtures, Mozart's late symphonies, Beethoven's SQ op 95, Schubert's Der Tod und das Mädchen, etc., so I definately believe that this re-orchestration would be sanctioned by Mahler.
In the 70s (or was it 60s) Duke Ellington made jazz arrangements of Grieg's Peer Gynt Suite and Tchaikovsky's b minor piano concerto; very enjoyable arrangements if you asked me. Anyway, Ellington was banned in Norwegian radio for this 'sacrilege' and Ellington wasn't played in Norwegian radio for a decade of so. What would had happened to him in Russia/Soviet Union I don't know, but he would probably be put away in the infamous Ljubljanka prison, had he been stupid enough to enter the Soviet Union.
My point is, that in the 'popular' music business, music is rearranged for other ensembles all the time, sometime the result is fine, sometimes not; so I can't see why it shouldn't be allowed to do the same thing in classical music without the risk of being beheaded. If you don't like the outcome, don't listen to it. We (or at least I) already accept the chamber versions of 'Das Lied' and M4 and the various arrangements/orchestrations of the M10 sketches.
Roffe