I find this to be a remarkable and exceptionally beautiful work.
Although we have no idea "how fast or slow" this piece should be played, I opted for a slow and sad approach.
The more I played it, I could imagine the drooping head of the Crucified Lord, as shown by the "falling" subject. I could see this work as an "interlude" as a grand setting of one of the Passions. Certainly, it seems to be a LOT more than just a little keyboard exercise.
For this performance, I've used only the Prestant 8' with Tremulant of the Bovenwerk. I've taken care to be expressive and formal at the same time, "stretching" out the many ornaments to the max, without impeding or interrupting the seemingly endless flow of the line - as the flow of tears from the mourners in some great Crucifixtion scene...