Yeah, I hate wank of any kind, so I very, very rarely give any kind of feedback that could be seen as confrontational. I took a day to compose a message to the author, got it proofread by my partner, and sent it to her in a DM, rather than leaving it on a public forum. That way, I wasn't shaming her in public, and wasn't really risking inflaming her fanbase. If she'd bitched back at me, I just would have dropped it, because, to be honest, 99% of the time, people aren't interested in being right. I mean, there's an otherwise good Sherlock fic that has the main characters use baby oil and condoms together, and I commented on that, because I have a sexual health volunteer background, and apart from another commenter speaking up and thanking me for pointing out the flaw, the author completely blanked me, even though it would have been an easy fix. One would think that if they went to the trouble of working in references to safe sex, they'd want to fix a catastrophic flaw like that, given how awkward working in condoms etc into a scene and keeping the tone still hot can be.