Which could then be reserved for "hyper-surrogates",
We don't need them.
referencing codepoints out of the 17 first planes, and assigned in a open registry for interchangeable semi-private uses,
There is no such thing.
such as corporate logographs and other visual trademarks (including the famous Apple logo character in the MacRoman encoding, or the extra PUAs needed by Microsoft in its OpenType fonts for Office...)
No. -- Michael Everson * * Everson Typography * * http://www.evertype.com
