Very Interesting! When did this come about?
We have had the Vls and Vapp less than 5 knots apart on approach on our 321s for some time. Up to now this has not materialised on the 320s, but just recently this too has been happening.
Some of our guys think it's to do with incorrect FMGS weight due to overweight pax! Thus the FAC providing the Vls is giving the speed aerodynamically but the FMGS is giving the Vapp from the inserted weight. By doing your procedure you will fix this problem I think.
Do you have a reference from Airbus for this?
