The main reason for separately encoding Coptic, rather than maintaining what we now recognize to be a mistaken unification with the Greek script, is that it is less useful to people who want to represent Coptic texts to have it be encoded as a variant of Greek than it is to have it be encoded as a distinct script.
Particularly as they regularly write text in both Coptic and Greek and this distinction is better expressed in plain text than in the font.
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Michael Everson * * Everson Typography * * http://www.evertype.com
