I recently had a woman who had medium interest. Meaning she would text and chat but would balk a little when I offered drinks.
She mentioned wanting to go out on my boat and I told her that I was going out that weekend. She pulled the same "I will let you know if I can make it".
I said "No problem. If you can, great, if you cant thats ok too. Just wanting to make sure that you know its just as friends".
After I sent her that, she couldnt wait to go. She sent back "I really want to go, I think it will be so much fun. But really? Friends?".
I said "Hey look, I offered dinner/drinks and it never worked out. I dont have a problem with you jumping on board when I am already going out on my boat but its best to keep it as friends at this point".
After that, it was like game on. It was like when I said "as friends" she couldnt take me rejecting and withdrawing my previous offer for dinner.
This chick has a 9 face and a solid 8.5 body. I am not saying this works all the time as some chicks will just lose attention completely because they cant string you along as an orbiter at that point and they already know their interest isnt going to change.
But if a chick is interested and playing a little hard to get, just withdraw attention, never chase, and try the "you're probably right. We would do so much better as just friends".
And you will, because if she isnt putting forth the effort for your attention she doesnt deserve it. And as just friends you will have no problem giving her no attention. Just like other "friends" lol.