Shodowfield question

Good day my fellow Archons I have a (probably very dumb) question regarding the Shadowfield of the Archon , I'm aware that wounds / saves must be allocated to the Bodyguard unit first , so the Shadowfield only kicks in once he is all by himself , turning the Archon into a though to kill Action monkey/Screening unit , right? Or am I missing some interaction where the unit can benefit from it aswell?