1 free runner and 1 free tackler is even numbers. 1 free runner and all tacklers blocked is a numbers advantage.
Optioning a man is basically blocking them mentally. Having a lead blocker on that man creates the same numbers situation.
OK, I get what you're saying from a definitions perspective.
But from the perspective of matchups of athletic ability, I'm not sure that works as well. 1 free runner and 1 free blocker may create a match-up of athletic ability, or it may create a situation where it's impossible for the runner to gain yardage without something extraordinary happening. It's a question of velocity and position. Well, and comparative athletic ability, I guess. But 11 kindergarteners and 1 free runner is a numbers advantage for the runner.
everyone blocked and 1 free runner is a numbers advantage IF every single blocker manages to block for the time they're needed. That's why you want a really fast runner, so that the smallest possible number of defenders can get to him, and then you try to match your best blockers with the tacklers most able to tackle the runner if they get free. You select those match-ups so that you're most likely to win. Every one of those critical match-ups is one on one.
Using a numbers advantage, I would argue, means having more than one person contesting the athletic ability of a tackler. That can mean a double-team on the line- if the defensive lineman is the incredible hulk, well, then you make him overpower two people instead of one. Or, in an option situation you have one tackler attacking two runners. He can be NFL hall of fame material but as long as the runners maintain good position he can't get both runners or prevent them from exchanging the ball.
That's what I was thinking in terms of a numbers advantage.