I think there is a reasonable case to be made for treating modern Hebrew and Biblical Hebrew as separate languages for pretty much all purposes. The existing codepoints with the fixed position combining classes work fine for Modern Hebrew, and there's no reason that they should not continue to be used for that language. I would seriously entertain the idea of re-encoding *all* the Hebrew marks, along with non-Tiberian vocalisation marks and anything else specifically needed for Biblical Hebrew, in a separate block, and deprecate the cantillation marks in the Hebrew block.
Speaking as a member of WG2, I do not think that we should encode such duplicate characters.
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Michael Everson * * Everson Typography * * http://www.evertype.com
