OK, OK...
Now most textbooks do credit the Romantics (especially the avant-garde of them, that is Liszt and Berlioz first, followed by Wagner) with thematic transformation as a compositional tools, am I wrong?
Why makes it so different from what previous composers had done?
I mean, if you take any set of variation from the Baroque or Classical periods, what do you call what they do? They take a theme and make it go through a serie of transformations, whether, rythmic, harmonic, melodic (although the original idea is still hearable) etc. Like Beethoven's Diabelli : the original waltz appears at times playful, heroic, pathetic...
Maybe the main difference is that previous composers use that tool within a very sectional form (like theme and variations form : here is the theme, then variation1, 2, 3 etc.) but the Romantic use it very freely with no care for sectional forms (if you listen to Liszt concerto #2, the transformations appear suddenly, no one has announced : "here is variation #3"), which makes their composition more naturally flowing.
What do you think?