I think if you go in with a frame that you're the opener and then some woman opens you, it messes with your mind. You might want to use lines like, "hey, slow down, I only just met you." that let her know she's being too aggressive. It could also be considered a neg, and might make her more interested in you. Nice problem to have.
Bear in mind, if she's opening you, you can jump past a big chunk of your usual Game. If she's really all over you, why not suggest the two of you go someplace more private. If you still need to build comfort first, do that, but feel free to let the conversation get sexual and see what happens, being ever ready to back up if need be.
Interesting question. I want to hear how others deal with this. I can honestly say that most times when a woman has come on to me it took me a while to get my act together. It just scrambles the circuits for a minute.
One more thing I just thought of. You might look into NLP. It would be nice to have an anchor ready for this situation. Just a thought.