I'd think Graham means spirit more than ki. Ki is neutral and can be used either way. Intent a bit higher than ki, spirit higher still. You can still use soft techniques and blending and what not but ultimately leading to uke's demise. Those soft skills while physically its not violent, comes with violent intentions.
True aikido goes beyond soft skills, but to ingrain a better spirit in oneself. One that doesn't have cause to harm another, this leads to anyone seeking to harm him to ultimately end up fighting themselves. But since Graham likes lone wolf so much, he should look up the chapter on killing Buddha on what I meant about natural violence. He doesn't want to, he just does.
Just to clear my view or my understanding for you.
For me Ki is spiritual and neutral in as much as it is non-resistive. But neutral cannot contain harmful intent.
So my view on neutral is very different to yours I would say. Thus it doesn't mean 'without' for neutral is active. Thus Ki is active, love is active, kindness is active and all are neutral. Being non-resistive they are infinite and don't 'choose' so to speak and thus the saying you can love your enemy.
Lone wolf I would say is already motivated by bad intention, purpose a decision for revenge throughout. If he looked inside himself, beyond the numb facade he would indeed find he does wan't to and beyond that if he looked further he would find in truth he doesn't.
He's trying to be as a robot but in so doing hiding and destroying his true self, a self that feels betrayed.
Such is my view.