Gosh! Well, as you'd realise by now, I love porn and sex, too. I also love research, whether virtual or actual. And I am constantly amused by how much information on these sorts of things is available on Wikipedia, let alone on any other source.

Though, like anything, I still think there's plenty of room provided by personal judgement and experience, and characterisation.

For example. I don't have direct experience of D/s, but relied on some Wikipedia-related research when I was writing a fic. I chose to use a detail there that I felt fit well with the characters and where they were on their own journies. Someone said, as they were perfectly entitled to do, 'No, I know what I'm talking about, and it doesn't work like that.' I totally respected their opinion, but I still thought it right for the characters and the fic. And obviously whoever wrote that bit of Wikipedia thought it did work like that. So I thanked my beloved reader as kindly as possible, and left the fic as is.

For example. While we're being all TMI here. I do have experience with anal sex, and have never had any need for lube, right from the first time, and even when it's been infrequent. At times it was a little uncomfortable, but it was never painful. So while YMMV, I have felt that I can write such scenes - again, if it fits with the characters and the fic. There are so many factors to take into account, including the characters' attitudes to sex, to safe sex, and to each other, how experienced they each are, and so on.

So, I appreciate where you're coming from, but I still think there's more room for variation in sex scenes than you're asking for here.