This version differs structurally from the published Grosses Concert-Solo, thus revealing the existence of interesting material for a study on the genesis of Liszt’s gradual innovations in constructing a large-scale musical organism, which were to come to full fruition in the Sonata.
The fact that the solo Grosses Concert-Solo has been overshadowed by the later two-piano version has obscured the importance of the former as one of Liszt’s largest and most ambitious original works for the instrument.
The Grosses Concert-Solo anticipates several of the most salient features of Liszt's undisputed masterwork, the Piano Sonata in B minor, namely the nonprogrammatic "four-movements-in-one" form.
Since this afterthought of Liszt does not quite agree with the initial intentions, the result is a somewhat loose rhapsodic structure with interlinked sections held together by a few insertions.
In contrast to the Grosses Concert-Solo the accompaniment figurations in the sonata are permeated by thematic allusions resulting in a more logically compelling development of ideas.
It is typical for Liszt that he did not destroy the earlier solo work (Grosses Concert-Solo) but rearranged it in the two-piano version Concerto pathétique.
Such a Konzertstück (concertino) form seems to be indicated by the title Morceau de concert [sic] (pour piano sans orchestre).
Liszt’s later addition of the Andante sostenuto part to the solo version results in sectional tempo (and mood) changes somewhat related to a baroque concerto.
The two-piano medium is excellently suited for projecting this concert style (also recognized by Stravinsky's Concerto per due pianoforti soli or Busoni's Duettino concertante).