Ok here is my observation on A320:
when on approach assume AP on, and descending spd at green dot.
select flap one how does the a/c decelerate to S speed ?(remember power at idle): by increasing pitch attitude as in any a/c
Next you select flaps 2 now there is a huge change in target speed from about 185 to about 140,and with power at idle the a/c has no choice but to pitch up* to acheive Fspeed.agreed she doesnt do it smoothly enough
*except during G/S star because the priority for the A/P is to first capture G/S then to slow down to target speed
