when ALL IAS are unreliable "sécurité du vol" must be considered "affectée" and 5° NU/TOGA drill MUST be performed.
I'm with PJ2. That isn't smart to apply that by rote in all corners of the flight envelope.
Short Sea Story. (I'm USN Ret)
Once had an instructor that demonstrated the approach to stall by forcibly unloading the aircraft to the point that g was actually fairly negative. (I acknowledged the procedure, but thought to myself, "No way in H#ll that I'm going to pop the stick forward like that."
Later I was on a 4 plane tactical hop, 2 students versus the instructor and another student. I was leading the student section, and we forced the instructor into an overshoot and split the flight so that my wingman was now on the instructors tail.
Instructor was embarrassed and tried to shake off his new "wingman". He went over the top of a loop at very low speed with my wingman in tow. Inverted at the top of the loop, my former wingman saw his airspeed at near zero and forcibly popped the stick forward by rote as he had been trained. Result-a very pretty and stable inverted spin that continued all the way to the ground. Fortunately his ejection seat worked as advertised but I was afraid we had lost him for quite a while.
End of Sea Story.
I am very suspicious of things you do by rote.