Being reactive will kill your game.
Life is a lot like chess. We always think that we are making the best move (who would make the worse of two moves?), so generally it's not the move that's really wrong (that's just a symptom), it's the thought process that led to the move (the action). This is why two people could use Love Systems material and yet won't have the same results. It's not the material, it's the thought process that lets us know when to deliver what material and how (in chess it would be what move to make and when).
You will always have to react (that's how the universe stays in balance: action / reaction), but how you react is up to you. Here is my thought process for dealing with people after I have a stimulus (action) that prompts my reaction. I examine the following:
Lower Social Value. Is the person of higher or lower status than me in my mind? It's important to recognize when you're reacting to a person of lower social value, and that can allow you to be neutral. After all, why get overly involved in such a person? It's very easy to be non-reactive with people of lower social value because they don't have value to you.
Higher or Equal Social Value. Pretty much every interaction we have with a woman is going to be because she has some kind of value (whether she's a 5 and you're alone and using her for social status by making her laugh, someone's friend you're making like you so you can get the woman you want, or other men you are befriending), there is a reason we are in the interaction in the first place. There's no reason that I can think of why you would be in an interaction with someone who has zero value. And that's where the problem is; we want something from the interaction so we are more likely to react emotionally.
If the woman shows her positive qualities, it's easy to respond by showing that you're interested because this is the behavior we want. It's when the women shows that she is not interested (the behavior we don't want) that we tend to react emotionally instead of rationally. Personally, I can feel when I am getting emotional and I embrace it. This because once I fully understand what is happening and why, I can just discard it and go back to being rational (much like dealing with approach anxiety, I feel the fear and just do it anyway).
In dealing with reactions, this is my advice:
Always have a better default/canned response
Be assured of your state of mind
By doing these three things I feel that I will never respond emotionally because I will always be way ahead in the interaction. I will control the dynamics and the underlying meaning of the interaction, and will react the least and thus have higher value.