Cold-Calling

This week I attempted to use the Cold-Calling method of questioning in my class. I am very torn up about the results of the particular method. I started by writing down my students' names on index cards, and pin-pointed the places in my lesson plans that I would use the cards to act as a method of "randomly" calling upon a student to answer a question. When I got to those points in my lesson, though, I would start to ask the class to shout out an answer, but would then remember that I was holding the cards in my right hand, and would have to slur my sentence, back-track, and explain my new method of questioning. The students did not seem to have any reaction to me using the index cards, and even when I would say, "Mr. Doe, could you please explain to the class what the first step in problem five is, " kids would raise their hand and shout out the answer. Again, though, I would specify, "Mr. Doe," and all those who had just shouted out would understand that I would not acknowledge anyone but Mr. Doe, and they would refrain from speaking. However, I find myself doing the same thing even when I'm not using the index cards. If I ask a question in class, I always expect at least half of them to shout out the answer. Sometimes I'll let the shout out suffice, other times I'll listen to the shout out, but then specify a single person to repeat their answer. The cards seemed to have the exact same effect. I suppose one purpose of the cards is to give an atmosphere of randomness, and make the students feel as though I am not playing favorites and that there's always a chance I'll call on them. This makes sense, but I hope to give that impression regardless of having the index cards in my hands or not. In fact, I found that even while I was looking at the cards, I might draw a person's name from the deck, decide that I have already heard "enough" from that person, and play it off as though I had drawn someone else's name.
In general, I like the intent behind the method of Cold-Calling, but I feel more comfortable calling on people randomly, and not having to look at a deck of cards. Maybe if I practiced the method a few more times I would become more comfortable, but the first time I tried it I found it to be more distracting to me, and I was more focused on the cards than the students. Like I said, though - Very good intentions I the method itself.