As I described the inverted veer as power blocking from an option look, let's first look at how "counter trey" is blocked. "Trey" is a bit of a misnomer, as there often isn't a trey block, but it is the most common type of double team that comes from this blocking scheme and thus it is called trey.
Trey is a combo block from the playside PSE (playside TE) and the PST (playside OT) to the MIKE or backside LB. Deuce is a combo block from the PST and the PSG (playside OG) to the MIKE or backside LB. Ace is a combo block from the PSG and the C to the MIKE or backside LB. For many teams, the FB will typically lead the defense to the ball. The same is said for a typical counter play, where the FB will counter step and lead the defense to the ball. But on a typical "Counter Trey" the offense will pull two of the OC, BSG (backside OG), and BST (backside OT). The first puller will typically used to seal the playside EMOL inside (or kick him outside if he gains too much depth or width) and the second puller will pull up through the hole and lead to the playside LB.
Well OSU is running this by using the read option like the FB again. They are using the read to block the backside DE. In general, OSU will pull the BST and the C. The reason you pull the C is for multiple reasons: he's closer to the playside and will be more effective sealing the EMOL; the play is run from gun so it is easier for the C to pull compared to the play being run from under center; it messes with the defensive keys by not pulling an OG as you typically would to the playside.
But like Counter Trey, it takes advantage of fast flow from the backside so they can't overload the playside.
And the give: