I enjoy this thread, but this is painful to read.
I think the idea that people make their own choices is a fairly logical conclusion to reach. Realizing that there was really only one possible choice, and therefor no choice at all can be a little mind bending.
Here is what I can come up with for a simple example of how this works. Imagine a simple pocket calculator. You take it out and turn it on. Now let's take a moment in time and call that state 0. This state includes every possible variable about that moment in time. From state 0 you press the buttons '2', '+', '3', '=' and the calculator then shows 5. No matter how many times from state 0, if you follow the exact same procedure, you will end up with the exact same result.
Now, let's take the same idea and expand on it. You are about to walk into a store, but there are two doors you can go through. Now let's create state 0 again. From state 0, you can decide to go through the right door, or go through the left door, or even go through neither door and leave. So let's assume you chose to go through the right door. If we reset things back to state 0, you will choose to go through the right door again, because you've already shows that from a given state, that's the door you will choose.
Now if it were me at state 0 instead of you, I could choose the left door and not the right door, but then I would choose the left door if things were repeated. So the idea is that we each maintain our individuality, but from a given set of circumstances, there is really only one way each of us could act. Because of this, while you think about things, and act a certain way, it is impossible for you to act any other way.