It is most commonly used to refer specifically to the ad hominem abusive, or argumentum ad personam, which consists of criticizing or attacking the person who proposed the argument (personal attack) in an attempt to discredit the argument. It is also used when an opponent is unable to find fault with an argument, yet for various reasons, the opponent disagrees with it.
It does seem a worthwhile post. This may contribute towards the perplexing aspect of intimidation. It is as good as explanation as I have found.
Concentrate on the facts.
However, it seems from the conflict resolution advice, that such a procedure is doomed to failure.
On Establishing Facts
1. Establishing objective facts will usually not resolve a dispute. Objective reality is unlikely either to be the cause of the problem or the source of the solution.
2. Each side in a disagreement may contend that the other was at fault in causing the problem.
3. The key to resolution is not necessarily the objective truth but what is going on in the heads of the parties. The facts, even if established, may do nothing to reduce a conflict.