I have tested many time shadow strike vs not one on one vs none, they score there is no significant difference, so I still believe that it is just random. You can be lucky with an AMR or ST without SA, that will out perform the one with SA and vice versa.

Nordeus should add like a +5% chance probability or so to those mentioned SA.

I only have those coming from the box with SA's. Generally IMO MC with SA performs worse and scores less (not when dedicated for freekicks/penalties or so of course)