A simple argument for penal substitution

There are fine-grained exegetical arguments for penal substitution by scholars like Thomas Schreiner and Simon Gathercole. But I'd like to sketch a simpler argument:

i) In the Gospels, one individual (Jesus) does something for the benefit of second parties. That's a one-to-many relationship. He takes an action for the good of many. Not something they do by themselves and for themselves, but something one individual does on behalf of others. That, in itself, is vicarious. A benefit accrues to them as if they themselves did it, when in fact someone else did it. And that's not an incidental consequence, but by design.

ii) And it has a more specific dimension. He suffers punishment. As a result, those who trust in him won't suffer eschatological judgment.   

The principle doesn't turn on a particular verbal formulation in the NT, or picturesque metaphors. It's operates at a more generic level.