The Romantic era in music was to accept the centrality of this practice, codify the form explicitly and make instrumental music in this form central to concert and chamber composition and practice, in particular for works that were meant to be regarded as "serious" works of music. Various controversies in the 19th century would center on exactly what the implications of "development" and sonata practice actually meant, and what the role of the Classical masters was in music. It is ironic that, at the same time that the form was being codified (by the likes of Czerny and so forth), composers of the day were writing works that flagrantly violated some of the principles of the codified form.