I think there's two variables here were giving full respect to: the type of woman and the type of porn. I guess you could simplify and say there are two types of women who ask "What kind of porn do you watch?" the kind who are genuinely curious and unthreatened by pornography, and the kind who are looking for reassurance that you dont watch porn. I think the latter equate nicely with your analogy of not telling your girlfriend that her butt looks big in her pants, but I don't think those types of girls are the vast majority. Maybe it's just the company I keep, but I cant think of a single female that I know personally that is really bothered by the idea of her man watching porn. It's just common knowledge that most men do. I think lying to the former would just annoy her in that it implies you underestimate her ability to recognize this and the amount of security she has in herself to be okay with that. At least that how i'd feel.

Then there's the type of porn you watch. Yes, it probably wouldn't be a bad idea to lie to your girl if you watch max hardcore, meatholes or pissmops, with exceptions of course. But you, E Y, stated earlier that you watch rather vanilla type porn, so what's the big deal? Like I was trying to illustrate in my story, I was far more weirded out by the one boyfriend who had a ridiculously tame taste in porn compared to the others who I perceived as relatively normal. Of course i have almost daily interaction with men wanting to buy my fecal matter so perhaps by perception of what is normal is skewed entirely.