Are doubly augmented and doubly diminished intervals practical?

Question

In music theory when naming intervals, a lowered diminished interval is a doubly diminished interval (dd) and a raised augmented interval is a doubly augmented interval (AA). One example is a C♯ to a G♭ would be a doubly diminished 5th (dd5) and a C♭ to a F♯ would be a doubly augmented 4th (AA4). However, these intervals can be converted to their enharmonic equivalent so the make more sense so instead of having a C♯ to a G♭ you could write it as C# to F# and have it be a P4 and instead of having a C♭ to F♯ you could write a B to F# and have it be a P5. I have never actually seen a naturally occurring doubly diminished or doubly augmented interval I have only isolated examples in theory books. Is there ever any scenario where any doubly diminished or doubly augmented intervals are used in melodies or chords?

Answer 1

It's true, these are like monsters of the fevered imaginations of theorists. The only use I can think of for them would be as ornaments: imagine you are in the key of D minor. You compose three chords: D minor, D diminished (D-F-Ab), back to D minor. Boring, right? So during the diminished harmony let's have a little neighbor tone interval occur: Ab, Abb, Ab. The Abb is a lower neighbor tone to Ab. The interval D+Ab is a diminished 5th; the (momentary) interval D+Abb is a doubly diminished 5th.

I think you'll agree, it's a sort of "tempest in a teapot", and, yes, the same interval could be spelled D+G and we could all go to bed early.