Ordained Local Ministry in the Church of England

Ordained Anglican ministry is changing rapidly. Soon the majority of clergy are likely to be volunteers and, especially in rural areas, female. All mainstream Churches recognise that new contexts need new forms of ministry. Ordained Local Ministers (OLMs) are priests specifically called out by their local congregation and ordained to minister in that locality.
Half the dioceses in England and elsewhere in the Anglican Communion including Australasia, Scotland and North America have established formal schemes to enable this type of ministry. Some dioceses believe the process has helped to revitalise parishes and raise the spiritual temperature of congregations. Others have called a halt, believing their schemes have somehow gone wrong or have not 'delivered'.
The time has come for a calm assessment of available evidence about an experiment into which the Church has poured considerable time, effort and money over the last twenty years. Does it have ongoing value, or is it just one more bright idea that has flourished for a season and has now had its day?