Hansen obliged, in the genuine belief that sharing information is a legitimate and important means of helping referees get a better handle on how the game is being played. This is how rugby is, how it works. It is collegial and driven by a dual code of international sides striving to win, yet being conscious that there is a secondary need to support the wider development of the game.
This is why it is relatively common for referees to stay in the same place as teams. World Rugby appoints referees for Rugby Championship games and then it is up to the host national union to accommodate them. Commercially, it usually makes sense to place the officials in with one of the teams as there is often a sharper deal to be had.
This has been acceptable and normal practice in the past, but is presumably now going to have to be reconsidered. The game can't have it both ways.
The police in Australia continue to investigate a major integrity breach following the discovery of a listening device in the All Blacks' team room. However well intentioned Hansen's meeting was with Peyper, it still opened them to accusations of breaking rules and, when it comes to integrity, perception is always a bigger danger than reality.
Best solution? Accommodate the referees somewhere the teams aren't. That way there can be no impromptu meetings. There won't be any friendly chit-chat between players and officials in the lift and the opportunity for random situations to be misinterpreted.
If an official wants to chat with a coach about a previous performance, then it would be best if it was made through a formal request and all the relevant governing body managers notified. Keep everything transparent and with clearly defined process.
Yes, it will make rugby feel colder, more clinical and bureaucratic - almost a bit sad that adults with a passion for their work can't easily sit down and share it.
But separation is the only way to protect everyone from damaging accusations that have the power to destroy reputations and credibility.