 A common hypothesis made in the later half of the 19th century was that the piece was based on authentic Mozart material but constructed by a less skilled composer.Cecil B. Oldman believed that the work had stylistic similarities to Mozart's sinfonia concertante for violin and viola, K. 364, and that Eck was the completer of the work, writing in a footnote to p.1469 of "The Letters of Mozart and his Family Volume III"