It doesn’t occur in the McAlmon apartment, but many of Schindler’s Plaster Skin buildings have two-sided cantilevers, cantilevers that wrap around a corner. Some examples are
Figure 1 Oliver House 1933-1934
front corner above street level garage 1
Figure 2 Buck House 1934
overall front, house on left and apartment on right
Figure 3 Buck House
detail of front at Dining
Figure 4 McAlmon House 1935
front entry of the house (not the apartment) 2
As always, Schindler puts the drama up front. These two sided cantilevers are at, or on the way to, the front door.
Applied to our sample building, a double cantilever looks like Figures 5 & 6.