I've done this, and even more: very often lately I've written a response on HN, let it sit for a few minutes, then delete it.

Not because I think I'm right (I think I'm aware of my flaws), but because I realize I don't feel like arguing about it, maybe my reply is closer to a belief of mine I've no wish to defend, and I suspect any snarky replies might incite a bad back-and-forth that never ends well online, bet it HN or elsewhere. So having gotten the reply out of my system, I delete it before anyone has a chance to reply.

Somehow my brain gets tricked into thinking I've replied, and allows me to drop the whole conversation in peace. It's a neat trick.