 Bogatyrev studied the notebooks, sketches, the piano concerto revisions, and Sergei Taneyev's reconstructions of the "Andante and Finale", which form the second and third movements of the 3rd Piano Concerto in its complete form, and was able not only "to deduce a great deal of what Tchaikovsky seems originally to have intended for his symphony ... but was able to reconstruct a fair semblance of how he might have completed it.