you are missing the point a smuch as she is.
you want to put them on the "point". make them make a split second decision... because you will get the truth.
what the **** have you accomplished by getting an email address, when if she wanted, she can just hit the spam button, never to see or hear from you again?
Look woman, if you don't want me to talk to you, tell me you don't want me to talk to you. I'm a big boy. i can take it. You aren't going to hurt my feelings. there are women for different reasons I don't want to talk to. That's life.
Don't be so afraid of rejection that you have to always leave yourself an such as a spam box infected email address
I mean listen to your rationale
lol, what woman says "damn, I don't like him enough to give him my phone number... but I guess I could give him my email address"
and when you leave her presence, do you honestly, deep down, think you are going to talk to her again?
HELL NO.. but you just had an interaction with a woman without getting rejected, or bruising your ego, which is what it comes down to.
I can take rejection... And the woman who GIVE you their numbers, you know there is some interest there
you can't take the good and not take the bad. Or in your case, you can't take the good and try to hedge the bad