Ha ha nope my instructor and I had a long productive sit-down after that. Instrument ride went great. It was that !@#$%&* PO 180 that got me LOL!

Hey! I'm also a 41 y/o career change pilot. Congrats on not just talking about it but DOING IT! Got my Commercial Single in January, have my CFI checkride on Tuesday.

I LOVE Power-Off 180s. Currently on an unbroken streak of 19 successful PO180s in a row. To get to this comfort level, I did the same sort of thing you're doing, practicing the maneuver in lots of different conditions. Here's my tips on locking it down. Disclaimer: advice is based on Cessna 172 aircraft.

1. Setup the same way every time. Same airspeed, same altitude, same distance/sight picture from the runway on downwind. Once you're abeam of the landing point, pull carb heat & power and pop a notch of flaps (10 degrees). Turn base the moment your airspeed matches best glide speed (should take 3-4 seconds) and trim accordingly for ease of control. From base you can correctly gauge if you need to dog-leg it directly to the runway or box it out to lose more altitude (remember to take wind into account by looking at the windsock on downwind EVERY TIME).

2. Specifically practice coming in too high and coming in too low on final. This way when you make the wrong call on the base leg, you've still got options on final approach to salvage your landing.

Too High: Flaps to 30 degrees, put the plane into a slip and drop altitude like a pro. Once you're out of the slip, feel free to drop in those extra flaps (don't slip in full flaps configuration, it's a bad habit). When you're approaching the target landing spot, don't be afraid to put her down hard. Just make sure you're not coming in with excess speed, use the slip to bleed off altitude and keep your speed in check, ride the slip all the way down if you have too, DON'T try to land at high airspeed. You'll bounce, nosewheel-barrow, prop strike or porpoise (in other words, you'll fail).

Too Low: I can explain this to you all day but you won't get it until you TRY IT. You're on final, you have 10 degrees of flaps in and you're coming in too low/too slow. As long as the approach area is clear of obstacles, push the nose down and increase your airspeed from 70 mph to 80-85 mph. Yes, I know your aiming spot is now grass, that's okay. HOLD THIS. You're going to round out once you're in ground effect (yeah, LOW). Don't flare. Go to full flaps once you're in ground effect. The extra airspeed plus the additional lift being created by your flaps in ground effect is going to float you down the runway. Slowly increase back pressure to stay off the ground until your landing spot is past your rear wheels, then gently release some of that pressure to touch down.
Try this approach and just see how long you can keep it off the ground. See how far you can make the plane float. Once you've got this technique in your tool belt, PO180s will hold no fear for you. I honestly love coming in a little low on these now. This is exactly how I executed the PO180 at my Commercial Checkride.

Good luck! Maybe I'll see you in the Regionals!!

What does the airplane manual state about slipping with flaps?
Why would you call it a bad habit?

In my post I listed a disclaimer that my advice was specific to the Cessna 172. The 172 POH specifically advises against executing slips with full flaps. I know some people still do it but disregarding instruction located in an aircrafts POH is a bad habit.

If I remember correctly it creates a flutter.... harmless but can freak out the pilot and pax... so they recommend not doing it.

Something about the way the air deflects off the wing in full flap configuration and hits the rudder when in a slip (applies to both forward slip and side slip). So, we just don't exceed 30 degrees of flaps if we intend on using a slip.

I’m a CFII and have experienced the “phantom flutter” in both C150’s & C172’s with 40° flaps in a full forward slip. Slightly unnerving the first time (feels similar to, but much less violent than driving over the asphalt vibration strips on the sides of highways), but easily rectified by slightly easing out of the slip to more like an 80% full slip... I do agree that the best approach to get proficient deadsticking is by slipping with 20°- 30° flaps and then be dropping final flaps as you’re easing out of the slip...

I was taught to avoid it so as to not mistake phantom flutter for stall buffet. Or worse, mistake stall buffet for phantom flutter.

I completely agree- the only scenario warranting a full forward slip with 40° is an actual emergency where the field MUST be made... or a flight instructor wanting to truly understand the envelopes of the plane they’ll be teaching in...

Jay, no offense.
As I’m teaching an initial CFI I’ll give you the same answer I’ll give him…..what-does-the-book-say?
Not all 172’s are the same, there are many variations in many models.
Some have the same limitations or restrictions and others don’t.
First of all is it in the Limitations Section?
If not is it a Warning, a Caution, a Note or a recommendation?
For instance the starter duty cycle in a 172S is a “recommendation” and not a “Limitation”
Under Emergency Procedures 3.17 descent through cloud the recommended techniques is hands OFF the yoke and small corrections on rudder only. That is not a technique that I would teach for various reasons.
Since you’re heading for your CFI what you’ve been “told” in the past should not necessarily be taken at face value as the person telling you may have been incorrect, quoting the manual for a different sub-model.
Being a CFI is about knowing why and where it says so.
Slip with full flap when frequently done will cause increased and accelerated flap track wear because of the ‘chatter’.
Now since a lot of flightschools use clapped out jalopies its often difficult to tell as it rattles regardless of flap position.
The effect still needs to be taught as you don’t want a solo student experiencing this for the first time on a solo flight as they’re often less then perfect.

Back to the Commercial, in that check ride it’s about demonstration of superior airplane control. Needing a full on forward slip with full flap in order to not overshoot your intended touchdown point is not part of that, at least in my opinion.
It’s not about throwing everything at it including the kitchen sink.
If you find yourself in a situation where you need that you’ve set up the maneuver wrong.
Now a gentle slip for a couple of seconds to loose just a little bit of extra altitude shows insight and skill.
Totally different thing.