I'm all in favor of people flying precisely. We're all professionals and sloppiness is simply not acceptable from anyone given the responsibility of people's lives in their hands. For that reason anyone correcting VAPP for incorrect FMS calculations is fine with me.
However, we all know that Airbus (I won't speak of Boeing as I haven't flown them) would like thrust variation to be as few and as gentle as possible due fuel savings. And I'm sure anyone that has flown the 320 family has experienced being in cruise and suddenly having the thrust jump forward because the aircraft has reached cruise attitude minus 50 ft after a shallow decent in an effort to increase speed without adjusting thrust but which inevitably did not yeild a sufficient increase in speed (called soft cruise or something that like).
However, is anyone aware of just how the auto thrust behaves during an approach. Does it try to be gentle down to VAPP -5 Kts and then kick in hard, or does it wait for VLS? Or is there no difference at all? As for those flying manual thrust (rare these days I know) if you add 2 or 3 kts to give yourself more margin to VLS what is that saying about your trust in yourself. In a calm wind your VAPP should be VLS. And most checks call for a tolerance of only VAPP -5kts. What does it say of our own confidence in our flying skills when people do not have full confidence on the line to meet the standards they are expected to meet.