A "Leave Open" vote (or even an Edit action) is not exactly a counter-attack or offset to a normal close vote.
Instead it is a counter or ticker to move the questioncounter or ticker to move the question out of the close review queue, and back into the normal circulation of things.
Sitting in the Close review queue is focussed attention. Three "Leave Open" votes knocks it out of the rounds for a while so that the close vote ageingthe close vote ageing happens as quietly as running into the question outside of the review queues.