Would the GS mini function work incase any one or even both the Tower and Current headwind components is a tailwind?? Like if we have any one (Tower or current) component of 25 knots tailwind, would the system consider it as headwind of -25 knots or simply 0 knots?
It should not be done.. you will have a different computation of the Vapp by the FMGC which will affect your landing distance in return. Giving more headwind input in the perf page will increase your vapp and in turn increasing your landing distance.
No since aircraft is flying in Normal law during the approach as well, there are all the normal law protections available to the aircraft. But GS Mini is very unique to approach phase to cater for the continuous wind changes which is not available in the normal protections of the aircraft.