Krebs has presented us with a labeling system of admirable simplicity. Still, there are times when I wish it were a bit messier. Even in less straightforward situations, I would find Krebs's interpretive distinction valuable. Though this situation recurs in m. 91, it does not seem to me to be a separate layer, but rather an alteration within the existing layer. These are moments that seem intent on shattering the continuity of meter itself.
Any theory highlights some aspects of music and downplays others.
The danger is that metrical dissonance, usually slighted to begin with, might be seen as a kind of underground alternative to the legitimate world of tonal theory. At the very least, awareness of metrically dissonant layers can sensitize us to voice-leading readings that we might otherwise miss. In m. 87 there is a parenthetical interjection of a motive from the opening F-minor section. 1-2 and the following agitated delaying of the Kopfton . The preceding thoughts are not to be taken as criticism.