NorthSouth
In essence you may be sort-of correct but you/we are talking about Class D airspace where separation as such is not applicable between IFR and VFR flights and, with respect, it is misleading if you use that term. Having said that, many units will apply a maximum level restriction so that the VFRs are a known quantity and need only be taken into account when an IFR is climbing or descending through that level band or to obviate the need for traffic information where avoiding action is impractical, for example a VFR departure and an IFR in a holding pattern overhead the aerodrome. However, there is no authority for the application of 1,000 ft as such in those circumstances (unless there is a WT interaction), but neither is there any guarantee of the VFR pilot's height keeping accuracy! It always surprises me though that there seems to be little reaction from the light aviation elements that such restrictions are not cancelled promptly when no longer required for safety. The intention of establishment of Class D airspece is that VFR flights should be free to operate up to the maximum level, albeit with ATC clearance and relevant traffic information.
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