Of course the circuit will be bigger if a flatter approach profile is flown. Assuming you commence final approach from 500' AARP, that point will be significantly further away from the runway on a 3 degree profile than it will be on a 5 degree profile. And if the approach is making good 60 knots (that might be optimistic) you're looking at a huge increase in the amount of time taken to crawl down final approach. That also ignores the extra time flown downwind.
As for using 'approach guidance' at the ab initio stage - the aim (IMO) is to teach the kid how to use his eyes hands and judgement, not how to follow PAPIs.
Stable at a given height, remain within tolerances, go around if outside - sure! That works for any desired approach angle.
Training value is actually reduced at the ab initio stage in a piston aircraft when flying a 3 degree glidepath with full flap and 'high' power settings. I believe it is better to teach good elementary handling and judgement, and then the student has the required skills to fly any approach profile.
Last edited by Capt W E Johns; 18th Nov 2006 at 19:43.
Reason: Spelng