While the press seems skeptical and blogging commentators (see BabyBlue,
Matt Kennedy, etc.) have expressed some concern, I don't think there's anything out of the ordinary or surprising about this document. John Rees, as well as Norman Doe, have been talking about the idea of an Anglican common law for years, and I think that this document is simply one more in a long line of very fruitful studies. That it won't do what many people want it to do (or fear it will do) isn't the fault of the drafters.
Talk of a ius commune as a "fifth instrument" of unity in the Communion is worth consideration. I've already expressed my doubts about the venture, not because I see anything wrong with it per se, but rather because I don't see much constructive good in it. Any new structure that attempts to strengthen the bonds of unity within a communion would do better, in my opinion, to address why the bonds of unity already in place are seen as inadequate. Apart from this, I don't see the point in reinventing the wheel. Here's a snippet from my article, "Instruments of Faith and Unity in Canon Law", (The Ecclesiastical Law Journal 10 (2008), pp. 161-173, 169, emphasis added):
"The global order of a communion is not juridical, but rather a moral order. The moral interdependence of Anglican provinces has been described in terms of 'bonds of affection' or 'an implicit understanding of belonging together'. Unfortunately, the moral order of communion is often contrasted to provincial juridical structures in a way that renders it impotent. The moral order displays, 'a high level of generality' and is 'not binding' and 'unenforceable'. It is probably because of this perceived deficiency that a more coherent global structure of faith and order is being pursued, the two most prominent proposals of which are an Anglican ius commune and covenant.
Proposals for a global canonical order are understood to codify pre-existing provincial canons, or inter-provincial conventions. This being the case, however, the question is begged whether current communal structures are, in fact, inadequately suited to fulfil the needs of Anglican communion. Numerous difficulties arise when the 'bonds' of affection are described as 'non-binding', even if only a lack of legal obligation is intended, because this observation undercuts the non-legal foundation upon which communion is structured. While the instruments of unity are at most 'quasi-legal', communion ecclesiology has always retained this form and claimed its authority nonetheless."