DZ Problems
As i see it, the problems with an off airfield DZ is they cause another restriction to GA and are not subject to sufficient control.
This means another 'Zone' on the chart which is probably only active on an occaisional basis, but fills in, and restricts yet more airspace.
There is no good reason for this and a DZ should be made to 'fit in' with aviation not restrict it. Ad hoc non airfield DZ's are a nonsense and the CAA should realise this.I also suspect that there are few 'charges' made for this (unlike a licenced airfield) therefore little incentive to restrict asking for one.