I am perfectly happy if someone tells me that I am wrong on a matter of fact, especially if when I ask there is some argument to back it up. One of my IRL "catch-phrases" is, in fact, "touche, you win this round, my good man ;P".
However, that's not the kind of statement you made. To demonstrate this with a concrete contextualized example, instead of writing this response, I could have instead said the following: "well, people are entitled to their misunderstandings about discourse; I mean, I actually used to have the same wrong opinion you currently do, so none of us are beyond reproach".
Of course, that statement would add nothing: by your own criteria (We need to ask ourselves, "What understanding would my comment add?") I would have made a comment whose sole purpose is to throw in a bit of rhetoric for which the only realistic goals would be 1) to play towards audience members who agree with me and 2) to fluster you by belittling your opinion in a highly flippant manner.
In the case of your comment, it was even weirder, hence the response to the person pointing out "irony": you seriously took an article you posted about how people were making pointless comments over something you claimed wasn't important and used that as an opportunity to make an equally pointless comment about the exact same topic.
This, in one fell swoop, both demonstrated that you actually felt someone can be "wrong" on this specific topic (which is exactly what the people in these flame wars believe and is why they bother to spend so much time arguing with each other instead of just saying "that is your opinion, I have mine; opinions are awesome!"), while at the same time making it clear that you felt that a specific one of the two parties you were arguing about was on that "wrong" side.
I will then go so far as to say: how much more "ironic" can one man get?
(Note: I am pretty certain I have not participated in a single iPad Mini or Surface discussion; looking through my history, the last comment I made on a similar overall topic was in regards to the iPhone 5's larger screen almost a month ago, and I was commenting on a specific sub-argument, taking no overall stance on the high-level war people like to wage. http://news.ycombinator.com/item?id=4609243 I say this to disclaim quickly that I am not "in the middle of one of these arguments" and thereby emotionally flustered at being called out by your overall article topic.)