One must ask: to which "Churches" is this addressed? The answer that comes immediately to my mind is that one of them is likely the newly-formed Anglican Church in North America (ACNA).
In the newly-released Ridley Cambridge Draft of the proposed Anglican Covenant, we find this curious new provision under section 4.1, "Adoption of the Covenant":
(4.1.5) It shall be open to other Churches to adopt the Covenant. Adoption of this Covenant does not bring any right of recognition by, or membership of, the Instruments of Communion. Such recognition and membership are dependent on the satisfaction of those conditions set out by each of the Instruments. However, adoption of the Covenant by a Church may be accompanied by a formal request to the Instruments for recognition and membership to be acted upon according to each Instrument's procedures.
So, for instance, if the United Methodist Church wanted to adopt the Anglican Covenant for itself, it could? But if it did, this would not automatically make it a member of the Anglican Communion? If adoption of the Covenant does not make one a member of the Anglican Communion, how could a Church adopt a Covenant whose preamble begins, "We, as Churches of the Anglican Communion...solemnly covenant together in these following affirmations and commitments"? How could it affirm, in (3.1.4), that "we acknowledge four particular Instruments at the level of the Anglican Communion..."?
Of course, the United Methodist Church may have no interest in "converting" to Anglicanism. So one must ask: to which "Churches" is this addressed? The answer that comes immediately to my mind is that one of them is likely the newly-formed Anglican Church in North America (ACNA). Interestingly, the Covenant cannot promise that its adoption means admission to the Anglican Communion. But there is this distinct "carrot on a stick" feel to this provision.
So, basically, the deal is: Declare you want to be a full member of the Anglican Communion by adopting the Covenant and we'll get back to you.
It's an interesting "ecumenical" ploy. How it works in reality (and whether this draft will survive the ACC meeting next month--if at all--with this provision intact) remains to be seen.