MATZ listening squawks
In some congested areas of UK Class G airspace multiple MATZs add to navigational complexity and R/T workload. Perhaps a better system would be to allocate listening squawks and allow MATZ penetration without initiating contact with ATC.
An alternative (non-transponder) procedure might be to allow MATZ penetration without permission as long as you are listening out on the controlling frequency.
On a related topic, does Odiham need its MATZ stubs since most of its traffic is rotary?