I don't think you can split an attack in half.
Once you've started the attack and inflicted the strain/damage, you can't then decide to move closer before finishing the attack.
It does give other interesting possibilities though. It could be triggered in a 4-player free-for-all when one opponent injures another opponent and it isn't even YOUR figure doing the damage. It could be triggered when a hostile figure suffers bleed damage out of activation. It could be triggered DURING the end of round effects of some skirmish missions. Very interesting card... very interesting.
