As an example, and brief promotion for an oratorio that needs a home and a public premiere.   From “Moses at the Jordan River” synthesized recording in progress.   At a private workshop for the oratorio, the chorus sang the augmented sixth arpeggio without difficulty, but this was before I had analyzed how to tune it.    In the basic key of C, the C – Ab – F# italian sixth serves as V of V, leading to the dominant. 

“We Smote HIm”