The important fact lies in the last sentence; in all of my apps, I could so far safely and soundly ignore the fact that Surrogates are two characters long to es

The important fact lies in the last sentence; in all of my apps, I could so far safely and soundly ignore the fact that Surrogates are two characters long to establish character lengths. So by using UTF-16, all those apps are significantly faster than one that would have been based on UTF-8. And, to add to this, by the same nature, it is far easier to take char slices of a UTF-16 encoded byte array than of a UTF-8 one.