Responding to people's rants with "Cool" or "cool beans" really does seem to encourage them to delete it, I'm not really sure why. Maybe because it's a bit of a dismissal.

In real life I like to address this by calling that person, "Sport" or "Champ", for example the other day I was at work and this guy insisted that to read you simply have to internally sound things out. Now, subvocalizing while reading is a major impediment to speed and also to comprehension, which I have found to be true personally and which is backed up by the teaching methodologies I'm trained in for EFL. Now, dude just would not let it go and I was getting heated so I said,

"I'm sure you know best, champ."

From a conflict perspective, this is unproductive. Punches to the face are generally also unproductive. But, as has been noted by others during my formative years, if there is a button, I have to struggle mightily not to push it. And it felt good.

Anyway, later the dude came up to me with an amended argument and a peace offering, "we're both right" which is bullshit. I am right and he was wrong. Your lips should not move when you read.