GERSHWIN: "RHAPSODY IN BLUE," "I GOT RHYTHM" VARIATIONS, "CATFISH ROW." Alexis Weissenberg, piano; Berlin Philharmonic conducted by Seiji Ozawa. Angel DS-38050 (digital). Logic would apparently dictate that a Bulgarian pianist, a Japanese conductor and a German orchestra might attack this quintessential American repertory with less than idiomatic results. But logic yields to imaginative musicianship in these remarkably distinctive readings. Weissenberg proves both suave and animated in the Rhapsody (with the great clarinetist, Karl Leister, handling the obbligato assignment). The seemingly endless arch of the BPO strings lends uncommon stature to Gershwin's own "Porgy and Bess" symphonic suite, while Ozawa leads affectionately theatrical readings.