I think this should be nailed to every Airbus cockpit.....
It answers a lot of questions like this one - if you're not satisfied
with the speed its flying, take out the damn thing and control it
yourself.
In any case GWFK and AOA readouts in that PARAM ALPHA will
confirm whether the FACS are doing their stuff or not. If AOA is
reading something silly, go for FMC speed. If that's not healthy
then pull out the QRH and go selected with A/T off.
I do more selected speed approaches in this thing with A/T off
than any other modern jet type I've flown. GS mini has a purpose
but only up to a point.