Don't be a dick, be a dude.
If you care more about your so-called artistic integrity than the mental well-being of your friends, you're a dick. Don't be that guy. Use a blackout warning, and get over yourself.
If you're arguing for warnings based on the assumption that all people who have experienced X will be triggered by X, which I have just seen too much of in this whole argument, you're still a dick, and fuck you for thinking you can talk for me.
(As a sidebar, remind me not to go on a tear about how much I fucking hate the word "survivor" and wish I never had to hear it ever again.)
Even the assertion that we should warn for bad things because it might trigger someone who's been through them is missing the point, because people can easily get freaked out over stuff they've never experienced. The point of warnings is to stop the people you like from getting freaked out, whether it's going to send them into the hospital or just make them feel like they need a shower.
I don't even want to get into what we should or should not warn for, because it's preposterous to think that triggers and squicks are in any way predictable. There's some stuff that I think should just be auto-warn- noncon, dubcon, BDSM, abuse, incest- but the primary reason I've always warned for them is so that the vanilla people won't bitch at me, not because I'm afraid of giving somebody a flashback.
It's just the decent thing to do to tell people what's in a story before they read it, because they have a right to read what they want to read and skip what they don't. What is so hard about this proposition?!
I've always warned, and I'll continue to do so. I assume that most people who come to my journal aren't looking for stories where people hold hands and cuddle while they talk about their feelings, and since my main use for warnings is to find the dubcon with greater ease, I like to extend the same courtesy. Don't get me wrong- I also think warnings do a lot for keeping the people who read my fic safe, but I'm mostly motivated by the selfish desire to keep myself safe from criticism, and I have no qualms about admitting that.
And I'm not locking this post, but I'd appreciate it if people didn't link to it.