Hm. Data lock - checked. Dual eyes and brains - checked.
As eerie as it may feel, and all of us live through such moments, bets are that you guys did something different or additional to what you remember.
The GS mini does not react to headwind gusts as such. It reacts to the difference of the present headwind against the entered runway wind. One way to invalidate its calculations is to put a higher or/and gust included runway headwind (component).
QFU 200
W/V 160/11G16 140V200
MCDU 160/11 - correct (rwy hwc 8)
MCDU 200/16 - wrong (rwy hwc 16)
MCDU 140/11 - max GS mini effect (rwy hwc 5)
In the second example, the GS mini would not profess until steady headwind wind component exceeds 16 knots. With 160/22 the GS additive is correctly zero. Into the wind crab angle intensifies the impression something should be happening, but the math is still right. How momentary gusts are treated (=filtered) is not disclosed, but they must be at least a little.
B) I think adding a few extra knots to Vapp is horsesheets. Unless LDS weights are suspect. Stick to your old practice, unless it disqualifies you in the mind of the one-eyed superiors.
C) Adding an extra speed buffer in case of gusty, turbulent conditions is a fair and recognized practice. To avoid dynamic speed fluctuations taking you too slow at the lower extremes. Up to 15 knots ok not to complicate the flare too much. Do not forget to add those (and 5 for athr) in the LD perfo calcs. This is not for the flare-against-approach wind difference (GS mini takes care of that), this is for transient speed drops no matter the wind direction.