Other than encouraging debate, the assertion that GS (GPS-derived or otherwise) is better than AoA (essentially what the manufacturers are directing the pilots to concentrate on with their ‘pitch/power’ tables) is so flawed as to be laughable.
Using Airbus FBW procedures as an example, the onset of unreliable speed during steady-state cruise requires no immediate action from the pilots. Most likely, thrust will be locked as the FMS detects the anomaly, and the AP will disconnect. This is the aircraft ‘telling’ the pilots that it can’t figure out what to do, but that the last thing that it WAS doing was working, so now it’s over to the pilots. Hopefully then, neither pilot will do ANYTHING; the aircraft FBW will keep the aircraft flying at 1G, at a power that was safe.
Then it’s either a matter of calmly and methodically checking the QRH for the suggested pitch and power (if cruising at high levels - Airbus’ take being that at high levels, these events are short term in duration), or - if at lower levels - following the procedure to activate the BUSS (Back Up Speed Scale), where the PFD changes it’s presentation to a very easily interpreted AoA scale. This presentation allows very intuitive operation in all regimes, and during configuration for approach and landing.
There is no mention anywhere, in any of our manuals, about accessing the GPS data to determine GS. There is no mention about asking ATC what our GS is. No mention of GS, full stop!
Jet performance is so great, that their climb and descent capabilities (ie resulting in significant change in TAS and wind velocity over relatively short periods of time) as well as their high cruising speeds at high altitudes (with it’s possible significant change in wind velocity over short to medium distances) make any use of GS in UAS events unwise, ineffective and downright dangerous.
For those who might think Bloggs’ assertion is a good idea, I would instead encourage that they just follow the specific manufacturer’s procedures.