I have done exactly this! Given them fake credit number and other info, and kept them online for about 10 minutes. When I finally revealed what I'd done, I suggested they quit calling or I'd keep wasting their time if they did. I did this about 2 months ago. I've only gotten 2 calls since then. Before that I was getting 4-5 a week.
I received yet another call from these scam artists this morning (1138 hrs.) Prerecorded message from "Rachel of Card Holder Services" calling about my credit card but that there was nothing wrong with my account but I had to contact them about lowering my interest rate, yadda, yadda, yadda. In the past, I've pressed the number to be removed with no success. I've told them directly to remove my number because I'm on the DNC. They don't care. This time when I pushed the number to talk to someone I asked her why they persist in calling people who are on the do-not-call list. She was laughing and making some comment to someone other than me as she hung up the phone in my ear. I've reported these people to the FCC repeatedly and I never have any luck because the FCC is less than worthless when it comes to enforcing their own laws. By the way, if it isn't already obvious, these people are NOT from your credit card company and you'd be an idiot to give them ANY information about you, your credit cards, or your financial situation. Anyone who blatantly and repeatedly ignores the DNC is obviously NOT looking out for your best interest.
It won't work and all you did was confirm for them that they reached a "good" telephone number, ie a number connected to a live person who is also willing to fall for their tricks.