Re-read what I wrote:
Slipping into a short field over the tops of trees I might be "high", slipping, and slow.
As soon as I clear the trees I might reduce the slip, drop the nose, dive a bit, then float to the intended touchdown point.
We're not talking about transport category airliners here....
I did read your post and I think your point is that stabilized approach criteria rob you of flexibility. If they are improperly implemented your point is well taken, but when properly implemented it is not an issue.
The purpose of establishing stabilized approach criteria is not to limit flexibility, it is to establish rules to live by. Such as -- I won't continue an approach if my speed 50' above the threshold is more than 10 kts above my target speed. It forces discipline on the pilot.
No one is talking about transport category aircraft, though the concept is the same. The underlying inquiry is under what circumstances do you consider an approach no longer stable? What are the objective criteria that inform your decision?
Let's look at your example. As I understand it you are executing a forward slip to land at an obstructed and short field. You clear the obstacle and remove the slip. You find yourself where you wanted to be in space, pointed in the correct direction at the speed you want to be at. Fine, you land. Consider though what would you do if your speed is 5 kts too fast. Is this a stabilized approach or do you go around? What about 10 kts too fast? What about 15 kts?
If your limit is target speed (what the transport category folks call Vref) + 10 at 50', is there any reason it should be different from the short field at friendly private grass strip or an ILS to 14L at ORD (disregarding the controller telling you to go fast)? I'd suggest the answer is no since I would probably also use the same Vref for both but I understand that many pilots fly slower speeds to short fields than what they consider not short. But they can still set a limit as to how much above and/or below the speed they will accept. Bust the limit it is a go around, no trying to save it, just go around and try again.
Don't confuse approach profiles with criteria. Your profile for the obstructed short field and the ILS to the two mile long runway will be different, but there are still objective criteria you can identify to guide you in making decisions.
Here is a common profile that implicitly adopts stabilized criteria. Many pilots are taught this profile when flying a VFR pattern in a non-complex aircraft.
Downwind clean at Vref +20 a distance from the runway you can reference from the aircraft,
Abeam the numbers reduce to 1500 RPM (or the number you know works for that aircraft) , flaps 1/3 or 10 or whatever the first increment might be, engine controls where they belong - I'm thinking carb heat, maintain Vref+20 and the landing checklist complete to an appropriate point.
Turn base 45 from the runway threshold, add another increment of flaps, adjust pitch/power as necessary to be at Vref +15 on base descending about 500 fpm,
Turn final and add the final increment of flaps, adjust power as necessary to be at Vref +10 on final when aiming at your landing spot, complete the before landing checklist, which may be as simple as GUMP, at 200, 100 and 50' AGL check that you are Vref +10, -0 and land the airplane.
That is a profile that incorporates specific objective criteria for determining the stability of the approach. All of that is profile except for the final 200' which incorporates a very specific Vref +10/-0 criteria, bust the criteria its a go around. Ignoring the criteria is at your peril. You will float if you are too fast, this will sometimes lead to porpoising and broken nose gear, or you could imitate a SWA 737 and run off the end at MDW killing a kid in a car. Too slow and you land short, or stall while still 30 feet in the air or some other not pleasant result.
One last thought, I don't know why people resist adopting transport category procedures when the safety record of the U.S. airline industry is so superior to the light GA safety record. I'm not suggesting all policies should be adopted and all procedures implemented wholesale, but many, such as sterile cockpit and stabilized approach criteria are appropriate after adapting them to suit the GA operating environment.
To summarize stabilized approach criteria are not incompatible with flight profile flexibility, they simply establish limits beyond which the pilot will not go but rather will execute an escape maneuver.
Fly Safely,
