The idea of an hour-plus audio "discussion" of a symphony by a conductor is exactly the sort of insomnia-curing device that should eliminate the need for prescription drugs. However, tacked on as a bonus disc to this performance of Mahler's Third, Benjamin Zander's eloquent and impassioned ramblings about his excitement for -- and interpretation of -- the piece only serves to amplify the excellence of the two discs that precede it. Those two discs capture the enormity of this grandiose symphony, stunningly recorded early last year in London with a full and massive complement of musicians. Zander is obviously besotted with Mahler, and his deft understanding of the composer and the composition are in ample evidence in his leadership of such a large orchestra. In the same way that DVD commentary adds just enough perspective to the film you just watched, Zander's bit-by-bit breakdown doesn't stand well on its own, but as further illumination of a well-executed work, it's an innovative concept.