Secrets to Getting Girls: Emotionally Expressive Approaches

I was responding to a thread on the forum where forum member Arnav asked about how to keep cold approach conversations going beyond the first 30 seconds. He brought up difficulty dealing with girls he approached who only seemed neutral or polite.
Here’s a description of a similar phenomenon written by another forum member, RDRChaseMember:
So from my usual experiences with cold approach, they're usually I pay a compliment to her and try to open, and they walk away or don't stop to talk to me, fine. The other experience I get from it (though pretty rare) is that they do engage in a conversation with me enthusiastically, we're making long conversation, and I go for a number. Yet, when I follow up with them, I don't hear anything back from them.
It's almost as if I should expect general disinterest most of the time.
In one of my responses to Arnav (who wants to know how to keep cold approach conversation going beyond 30 seconds), I shared a secret to getting girls that veteran seducers all sooner or later figure out: that women reflect your mood right back at you, thanks to the power of emotional contagion. In other words, if you want a girl to respond a certain way to your approach, be that way on the approach.
Here’s what I told Arnav:
This is one of the magic tricks a good seducer has that regular guys don't: he can approach a girl and using nothing but his own expressiveness and her mirror neurons he can elicit what appears to be a high degree of interest from her right away. When I used to take guys out in-field and do demonstration approaches the guys would always comment after, "Wow, that girl was REALLY into you!" Sometimes she is, but sometimes she is just mirroring my approach, because that is what women do if you seem like a reasonably cool guy and you are being EXPRESSIVE. But get her to mirror you long enough and even the girls who weren't all that interested can start to wonder to themselves if maybe they are.
Today I’m going to let you in a little more on this secret of emotionally expressive approaches, that way you don’t have to wait until you’re 3 or 4 years deep in seduction before you puzzle this one out on your own (3-4 years in is right around when this one truly clicks for the average self-taught playboy).