This is the key part of the article. "IF a school comes across..." This implies that the NCAA would likely not hold a school liable for any infraction about which they did not know. As far as I know, when Duke comes across an instance of violation (perhaps such as the one described in the article), they would do something. There is already precedent for making students remove banners from quads, taking away signs at games, and shutting down groups. Again, it would thus seem unlikely that the NCAA would come after duke, since they had 'reached out to those fans to reinforce the ground rules.""If a school comes across an instance of this happening, it is expected that they would reach out to those athletics personnel, fans and boosters and reinforce the ground rules related to communicating with recruits," Cameron Schuh, an associate director for public and media relations for the NCAA, said in an email.
Then again, you never know with the NCAA.
I'm not particularly worried...unless jim calhoun is actually friending recruits on facebook...