She described his dick as "perfect" in context to her needs
No she didn't. Let's go back to what OP said.
I say that I really don't like big dicks - I'm really small, they intimidate me and I can't suck them for too long before my jaw starts to ache. That's why I like "blah blah"s dick, because it's perfectly average.
As in, completely average, totally average, 1000% average. Not "perfect and average". "Perfectly average".
She didn't say it fit her well, was better to fuck with, she just said it couldn't be more pedestrian and was easier to blow without hurting your jaw.
She used "average" to describe his size - not the quality of his dick or the sex they had.
Right. She never said word one about the quality of his dick or the sex they had. Just that it could not be more average. She described a part of him that some men will commit SUICIDE over losing as totally pedestrian. "At least it doesn't hurt!"
In your analogy, negative traits such as "boring" and "plain" are associated with average
This is what I've been trying to tell you this WHOLE FUCKING THREAD. It's how just about every man would have taken being described that way.
she legitimately prefers average-sized penises
And some dudes dig fat ugly women, but you show me ONE girl who'd appreciate being described this way.
In OP's scenario, however, X person likes Y because they prefer Y's trait (average dick) over Z's trait (larger dick). It's not a comparable situation.
This is not relevant. What is relevant is how the men who heard her drunken boorish outburst heard it. They heard it as him having a substandard, boring, replaceable, hum drum dick whose only possible benefit is that it doesn't hurt to put in your mouth for extended lengths of time.
A guy would hear that as "I'm used to being fucked way longer by way better hung dudes. But Joe Thumbcock here thank God doesn't hurt my jaw." It doesn't matter what she meant to say, I'm telling you what almost all men would hear in this exchange, and it's insulting.
"Average" doesn't cut it. A guy with an "average" salary isn't lusted after, the guy with the really nice car and the great job is. A guy with an "average" penis doesn't have anyone want to look at it or ask to ride it. The "average" guy has a relationship with a woman who happens to dig the "intimacy". It's the difference between a man whose heart skips a beat when he sees you, and a man who's with you because he likes the tuna sandwiches you've made him every day for thirty years. Be still my beating heart, wow.
The "average" height guy gets overlooked for the guy who's six feet and over. Women will talk about an "average" penis, you know, 8" in length.
A guy with average looks is considered unattractive. OkCupid has shown that for a guy, 8/10 in terms of looks is "average".
"Average" means you don't make the cut.