In lieu of a North Carolina versus Duke preview — do you guys really need me to break it down? — some vital information about why this game is pivotal to our season.

Recently, Sporting News’ Mike DeCourcy — otherwise, a good college basketball reporter — has been taking to the Twittersphere and to the pages of his publisher’s website in defense of the RPI. And not just in defense of the RPI. He’s also railed against other systems, such as Ken Pomeroy’s.

The thing is, he’s wrong. Like, real wrong. Like, “can’t make a good argument so I set up straw men and knock them down like Shawn Kemp at the Bunny Ranch” wrong.

And Pomeroy has a great article in Slate explaining why. Go ahead, click it, skim through it, then come back and get prepared to be really, really pissed off.

Here’s why this matters for Carolina: In recent days, both Florida State and Clemson dropped below the “RPI top 50″ threshold. Other borderline top-50 opponents, Maryland and Virginia Tech, were already below it. So going into today’s game, UNC is 2-4 against the top 50 in the RPI.

That could spell disaster. At least one major bracket creator (“bracketologist” is not a word) already has us as a four seed, in part, no doubt, because of that less-than-illustrious record.

Except it’s not ACTUALLY a less-than-illustrious record — if you use any system other than “RPI Top 50 wins.”

• UNC’s record against the top 50 in Pomeroy is 9-4 going into today’s game.
• But let’s say you don’t want to use Pomeroy because you’re like DeCourcy and think margin of victory shouldn’t count in making up a ranking system. Well, we can use the Sagarin rankings, which don’t take into account strength of schedule (DeCourcy’s biggest pet peeve with Pomeroy). UNC’s record there? 9-4 against the top 50.
• Carolina’s strength of schedule — compiled from the RPI itself! — is No. 15 in the country. (Compare that with San Diego State, which is competing with UNC for a 2 seed or a 3 seed. SDSU has a 7-2 record against the RPI Top 50, comprising three wins against UNLV, two against Colorado State, one against a Brandon Davies-less BYU, and one against No. 50 Saint Mary’s. But it has a No. 35 strength of schedule.)

Here’s the bottom line. If the committee decides to seed teams based on “how good are they,” I feel good about UNC getting a 2 or a 3 even if they lose to Duke today.

But if the committee decides to use a pointless, arbitrary system that’s been in use since Galaga came out? We could well be looking at a four seed, a dangerous first-round opponent (Belmont, the team Jerry Palm has us playing in the first round, is a nightmare scenario), and a completely unjustified Sweet 16 game against a one seed.

Don’t think today’s game matters? It does.