 In 1940, with the composer's consent, Horowitz created his own performance edition of Rachmaninoff's Second Piano Sonata from the 1913 original and 1931 revised versions, which pianists including Ruth Laredo and Hélène Grimaud have used.He substantially rewrote Mussorgsky's "Pictures at an Exhibition" to make the work more effective on the grounds that Mussorgsky was not a pianist and did not understand the possibilities of the instrument.Horowitz also altered short passages in some works, such as substituting interlocking octaves for chromatic scales in Chopin's Scherzo in B minor.