If you do an opinion opener and it is interesting enough you can get the girl to talk way longer than she should normally if you do this simple trick. Ask "why?" after she says her opinion, and then keep nodding, saying uh huh and don't break eye contact. Act really interested. When you do this you can sometimes get girls to even repeat everything they said twice. Make sure to act interested even when they repeat information. It is also a great way to gauge their interest. The longer they talk the more open they are to be talked to about other stuff. If you get a repeat story then its like getting a green light for more conversation. Also I've noticed coming up with lots of new opinion openers works better than using the same one. Whenever I come up with a new opinion opener I get a great response, and then it goes downhill from then on. I think it's because I am actually more interested in the answer when its new. Hope this helps.