

Sorry for the very tangent.
That speech frequency graph is a good visual of why for trans voice training, resonance is more important than pitch. The pitch is nearly the same, the difference is in which overtones are projected.
Where did you find it? I would like to read more about the methodology.
I was discussing real world sounds in open air. Yes, destructive interference is something you have to account for when dealing with sound systems. A speaker playing the same sound in the inverse phase will cause issues, but a group of people, as was the topic, will never be anywhere close that precise.
If the concern is safety, as it is in this example, the concern is the worst case. And the worse possible case is when all the sounds interfere constructively.
It’s not really a counterargument when I specifically said my logic of ignoring destructive interference doesn’t apply in “situations designed to cause it” like two synchronized sinusoids. Most people are not synchronized sinusoids.