Miss Mango

LOL never seen that one! That was great.
Yeah, how attractive you are is not the main issue, but it definitely greases the gears of interaction.

This statement, to me, is indicative of the problem for Avarage-Joe who says the wrong thing and inadvertently offends a woman.

What, exactly, is common sense? Can we specifically define it? Hell no.
In this context, it looks to me like a matter of social/gender aptitude. And some people simply have *learned* less of that than others! Those without much sometimes act in a manner that makes women (or anyone, really) uncomfortable without the capability of knowing that it's the response they'll get. They simply don't have the social experience to know where those lines lie. People don't pick up this 'sense' any more than they naturally pick up aptitude with, say, a computer. The lines are inferred through experience and trial & error, Common Sense (rather than specifics) as a guide is as reliable as the rules to Calvin Ball.

Should they have learned it? Yeah... It was their responsibility to, even though men have insufficient 'teachers' on this subject nowadays.
Should they be maligned for having not learned it? Well that's up for grabs.

In reality, whether your flirting is okay is mostly derived from helping women feel comfortable, un-threatened. That process is really socially complex. We often take it for granted.

This is actually a factor. Sometimes men have to take this into account. Kinda messed up, if you ask me.
Nonetheless, theres nothing we can really do about it. And women certainly face their own hazards in the courtship game as well... *shrug*