BuddyPress.org

Sorry, I forgot to consider the save functions.

Interesting problem.

There are a lot of action / filter hooks in bp-xprofile-classes.
You should be able to add the name field to the $_POST before it starts processing, so that you don’t need an input.
Or overwrite the ‘old’ name into that field value so that the new value isn’t saved, although that’s probably more confusing to the user than just hiding the input via css.