It's interesting to hear all these comments about flying the pattern when in fact circuits are an artificial training procedure which tries to combine two phases of flight into one. In reality a circuit is a departure followed immediately by an arrival, minus the joining calls and procedure.
Departure is all about getting as much air beneath you as possible and safely leaving the busy traffic zone. Arrival is about reducing your safety margin (height) in such a way as to give the best chance of making a landing under any forseeable circumstances. The exact height and distance for the arrival procedure, as stated by others, really is dependant upon local conditions.
So I would ask the instructors here: In order to properly teach a student pilot the correct arrival techniques, isn't it better to position the aircraft as if it had just joined on downwind, wherever that happens to be on your airfield ?
If that means extending a bit upwind and finishing the climb downwind to arrive at start of downwind at cct height and distance, then so be it......
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