Historically the Anglican Communion has comprised a group of Provinces and other Churches which have always worked together, prized their autonomy, and struggled to hold these two notions together.
Most provinces do not want to give up their autonomy, yet unless they do the Covenant will have no power to impose its wishes on them.
How does the Covenant resolve the dilemma? By signing it, member Churches would agree to give the Standing Committee of the Anglican Communion (SCAC) the right to be forceful against an offending member.
This creates a new basis of relationship between member Churches. The Covenant sets out (in sections 1-3) a statement of Anglican faith and order to which every signatory must consent. By whatever route Anglican Churches arrived at this point, from here onwards:
In adopting the Covenant for itself, each Church recognises in the preceding sections a statement of faith, mission and interdependence of life which is consistent with its own life and with the doctrine and practice of the Christian faith as it has received them. It recognises these elements as foundational for the life of the Anglican Communion and therefore for the relationships among the covenanting Churches. (§4.1.2)
How can all this centralisation be reconciled with provincial autonomy? By presenting the Covenant as a voluntary arrangement. To be a member of the Anglican Communion is to sign the Covenant voluntarily. Thereafter each province of the Anglican Communion may continue to act in whatever way it pleases - so long as no other province suspects or believes its actions to be outwith the provisions of the Covenant. The punishment for transgressing the Covenant is 'relational consequences': withdrawal from some, many or all of the international structures of Anglicanism (§§4.2.4 - 4.2.7).
Yet there is no difference in reality between being expelled and everyone else turning their backs on you. So a province may still act in whatever way it pleases, just as before, except that now it does so conscious that the other members of the Communion may act against it, forcefully, if it offends. Autonomy becomes a legal fiction.
For all its talk of being 'reliant on the Holy Spirit' (§1.2) and seeking 'to discern the fullness of truth into which the Spirit leads us, that peoples from all nations may be set free to receive new and abundant life in the Lord Jesus Christ' (§1.2.8), the Covenant is in reality an example of power politics. A significant minority of Anglicanism's senior leaders wish to punish or even expel The Episcopal Church (USA) and The Anglican Church of Canada because of their acceptance of gay people as full members of the church (and because of the cultural assumptions behind this acceptance). The Covenant gives them the right to do so and the SCAC gives them the means.
In this way a new foundation stone is to be inserted beneath the existing historical arrangements. Dispersed authority will be centralised as a conciliar and consensual church becomes a confessional church grounded on a new fundamental document.