> why not introduce a "seimhiu" character > whose glyphic representation is > either h-following or dot-above? > Primarily for Unicode structural reasons: > Unicode needs to say a character is > either combining or not.
It would be combining in both fonts. Although it is not usual in Latin script to place diacritical marks after the letter, IMHO there is no reason why it could not be done. So I can imagine following characters: for Irish: COMBINING H AFTER COMBINING SEIMHIU in modern fonts equal to 0307 COMBINING DOT ABOVE in archaic fonts equal to COMBINING H AFTER for Czech: COMBINING SHORT NABODENICKO in modern fonts equal to 030C COMBINING CARON in archaic fonts equal to 0307 COMBINING DOT ABOVE COMBINING C BEFORE <H><COMBINING C BEFORE> = CH P.A.