This post is to bring a comment from another neighborhood to my VOX-y friends here.
I've heard this phrase a lot: "when we all get in unison, speaking with one voice, then great things will happen"
In musical terms the unison is probably the most powerful of all musical tools, (but it is not the only one.)
The most famous phrase in all of music history is the opening figure in Beethovens 5th Symphony:
da da da da……….. da da da da………….
The whole orchestra is playing in unison, then something very interesting happens, Beethoven uses the same figure in different configurations and this becomes the harmony. Every instrument saying basically the same thing but in it's own voice and in its own way.
Even Beethovens 5th would be tedious to listen to if it stayed in unison the whole time, anyone who has studied the Gregorian chants, knows how boring unison music can very quickly become .
We do need to be in harmony as much as is possible and then there will be the times where we really need power, at that point the only thing that will do it is the unison.