@Dozy
Nearly but not quite:
The logic to trigger deployment of reverse thrust and lift dumpers required either both mainwheels to be on the ground [signalled by position switches on the landing gear torque links], or one mainwheel on the ground and a rotational wheelspeed equivalent to a ground speed of at least 72kts. Brake application depended on mainwheels spinning up to 80% of a computed reference speed, which is normally the rotational equivalent of ground speed, with special treatment during the transitional touchdown "spin up" phase. Because of the excess airspeed, the aerodynamic lift was much greater than normal, so that the ground reaction on the landing gear was very low. Taken in conjunction with the flooded runway, this provoked aquaplaning of the tyres in contact with the runway, so that they never got up to the required rotational speed, and brake application and the application of spoilers/ reverse thrust was delayed
Checking back on my source data another AI mod was to apply a small amount of dumper deflection immediately at touchdown, which killed enough lift to trigger braking but which was not enough to hamper a go around.