Err... this has been said before and was dismissed because warlords can see units stats. Unless there is some stats veiling/cloak that we don't know off, it's unreasonable.
And on that topic, i would like to know if now that the spell is complete Parson does have stats .
on the 'ruthlessness' topic: The sword gives 3 'feats': Leadership (we already know how it works), Combat (i guess now Parson does know something more than just 'pointy end away from user') and Ruthlessness, which he figured out how it worked when he got hold of it. I would guess we'll get to know more of it afterwards.
Though, when Parson was summoned, Stanley asked for someone who wouldn't have a moral case about being summoned, so i don't think that the completion of the spell would bring any mental/ethic issues to Parson.