I really think that most people do not understand what is really being spoken of when people use the terms "point and power".
Point and power simply means using the various controls at one's disposal to ensure that the constant point and the desired aiming point coincide and remain so.
Having sat through various instructor explanations (good and bad), experienced and ab-initio recently, not one could correctly draw the following;
Draw a diagram of the forces acting on an aircraft in steady straight and level flight at x speed (back of the drag curve close to the stall) and a separate one for y speed (same power but on front of drag curve)
All of them said that both drawings are the same since lift and and weight are the same in each because level flight and since thrust is the same then drag is the same since constant airspeed.
They are wrong.
The common issue is that in both cases the aircraft is being pointed at the horizon and the power is suficient to maintain the airspeed.
However what was lost on them was that while the flight path is horizontal, the direction of thrust is totally different in each due to the different attitudes.
Day after day students are shown diagrams of the four forces. Very few of them show the flight path.
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if the approach is started too high/close, the brakes cannot reduce the speed sufficiently
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That is not a function of "point and power" or "elevator for airspeed" mindsets.
It is simply a function of gravity and drag (or in this case not having enough drag to counteract the effect of gravity on the overly steep flight path that is required.
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when the brakes are opened they spoil the lift and create drag
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That is my understanding also.
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This is most readily seen in low level launch failures where cracking the brakes open will risk slamming the glider into the ground whilst still having flying speed.
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Could the real reason be that the flight path to keep that speed is steep enough to "slam the aircraft into the ground".
Ask yourself - should you do that, in the brief period before impact where is the constant point?
Just because the airspeed is x and the attitude is y it does not mean that the aircraft is travelling in the direction you expect - take a flat spin as a perfect example regarding attitude, gravity, drag and constant point!!
Regards,
DFC