CaptainMongo
True perhaps. As a matter of fact you could also say that the airplane will never fly fully on idle thrust down the precise pre-calculated profile. Either is low or high.
The trouble with the "slightly above" philosophy, to which I am a keen subcriber if allowed to do my own thing, is if the deviation becomes larger, the recovery options narrow and techniques become unavailable.
To a point where you just cannot do anything. Not a big problem because with the A320 the last anything you could do is around -7500 fpm or.-9000 fpm if in the mach segment (both no gear), provided your colleague uderstands what ECAM is for and what for it is not.
Another vote against the "slightly above" is the ATC side of the equation in 4D airspace. Losing height without the speedbrakes requires speeding up and getting there faster, meaning faster than the orderly flow of other traffic. That causes problems that will be solved at your expensense with extra miles. Even worse by asking to slow down SIGNIFCANTLY while fast and high. Complying will inevitably take you above the profile even more and about to miss that altitude vertical restriction to Approach Sector's TMA airspace resulting in ...
...you do not need to wait for it too long
.
a polite requiest to increase the vertical descent rate, the good old slow down and go down. Well, no surprise Sherlock, guess who could have prevented from happening in the first place.
Admittedly then, starting a little low is the less demanding option while staying asymptotically below the gliding path is the optimal solution. I am not sure what the ADPO discussed here feels like, whether or not I may have flown one equipped or not. Geesus, it was so long since the last flight I probably could not remember where the ignition keys go.