[extract] While the Governor-General has come to exercise most, if not all of the functions of the Crown in New Zealand, this has not necessarily resulted in a strengthening of the office. For the Governor-General is both strengthened and weakened by his or her position as representative of the Sovereign. They have the moral authority of the Crown, but share the vulnerability to criticism of that ancient office.
In this respect they came to represent the concept of the Crown in a way which the Governor-General never could whilst remaining an imperial official.
As a Governor-General will occupy the post for only some five years, they have felt constrained to follow, to a great degree, the example set by their predecessors. Like the Sovereign, to a significant extent the office of Governor-General has become institutionalised. It is in their constitutional and political role that this institutionalisation becomes clearest, and most significant. This tendency has been strengthened by the advent of MMP, but it has also encouraged a reappraisal of the office as part of the wider system of government. Most importantly, MMP has signalled reawakened interest in fundamental constitutional reform.
Available at: http://works.bepress.com/noel_cox1/2/