The foreground in Carl Schachter’s set of durational reduction graphs (cited in an earlier post but not shown, for copyright reasons) shows with particular clarity the two-against-three pattern that is basic to the interaction of right and left hands in D779n13: "the right-hand sets up a secondary meter of 3/2 against the 3/4 pattern of the left-hand part" (70). Such two-against-three patterns are by no means unknown in the waltz repertoire (they are favorites of Johann Strauss, jr., for example), but they are rare in early sets -- the first instance I have found after D779n13 is in Joseph Lanner’s opus 26, published in the early 1830s (still another reminder -– as if we needed one -- of how out-of-place the A Major Waltz seems in the Valses sentimentales).
Schachter uses the demonstration of the larger meter or hypermeter to make an observation about style. The cadences in this waltz hold an "anticipating 6/4," or a cadential 6/4 that is "in a weaker metrical position than the V7 to which it resolves." "Not frequent," these anticipating 6/4s do "occur from time to time, especially in music of the nineteenth century. Schubert and Chopin probably use them more than any other great composers, though examples can also be found in music by Schumann, Mendelssohn, and others" (73).
That cadential 6/4s might appear in both basic metric positions, strong and weak, is by no means surprising in the waltz repertoire, since, as we know, the figures of the common form of the valse à trois temps are displaced by a bar, so that one dancer's "bar 1" is the other's "bar 2."
Statistics for Schubert's dance music show that these hypermetrically weak 6/4s actually appear rather more often than "from time to time." In seventy two strains of the thirty six waltzes of D. 365, the most frequent progressions for the final three bars of a strain are I-V-I and V-V-I: these appear thirty six times. Next most frequent is the "anticipating 6/4" or "I6/4"-V-I; its sixteen appearances are nearly double those of an accented 6/4 placed in the penultimate bar (nine times). As rough statistics, these numbers hold up in his later dance sets, as well.
Among other composers, the anticipating 6/4 is a strong motif in Chopin's first waltz, op. 18, where it is used in all but two strains (see the first one below). After that, Chopin uses the device rarely, but in prominent positions (the cadence of the first strain or the first waltz) and especially–but not exclusively–in the waltzes in Ab major.
Lanner hardly uses the 6/4 chord at all; isolated instances of the anticipating 6/4 appear in later sets, such as Alpen-Rosen, op. 162 (twice). In the reduction of the first waltz below, note the ending of the second strain.
On the other hand, Strauss, sr., deploys the 6/4 at about the same rate as Schubert, and he prefers the anticipating type.
Strauss, jr., uses the 6/4 far more freely than any of the earlier composers, Tales from the Vienna Woods, op. 325, being perhaps a highpoint, as all of its waltzes use the 6/4 in at least one of their strains. Although he did occasionally use the anticipating type, most of Strauss's 6/4s appear in accented bars (fourth-to-last or penultimate). The graphic below shows the piano reduction of no. 5. The first strain uses the anticipating 6/4 (twice, actually, in its second phrase), but the second strain gives a prominent metric position to the 6/4.
