Please read Re^4: Marilyn Vos Savant's Monty Hall problem carefully, especially where I wrote
the host knows and will not open the door with the car (emphasis mine)
The knowledge Mr. Hall has and how he uses it is unambiguous. He always opens a door, he never opens the door with the car. and he always offers a switch. What's more important than the information he has is the information he provides by using what he knows in a predictable way.
Your memory is fooling you.

As is pointed out at Re^4: Marilyn Vos Savant's Monty Hall problem, the original statement of the problem when Marilyn Vos Savant gave it was, Suppose you're on a game show, and you're given the choice of three doors. Behind one door is a car, behind the others, goats. You pick a door, say number 1, and the host, who knows what's behind the doors, opens another door, say number 3, which has a goat. He says to you, "Do you want to pick door number 2?" Is it to your advantage to switch your choice of doors?

Note that how the host uses his information is ambiguous in that problem statement.

Furthermore most of the time when this comes up for discussion, the problem is even less carefully stated than that. It is typically not even specified that the host knows where the car is. For example look at the node that started this discussion, Marilyn Vos Savant's Monty Hall problem.

Therefore no matter how much you'd like to believe that you've never seen it poorly stated, you're wrong. In fact you've seen it poorly stated at least twice already today.

In reply to Re^7: Marilyn Vos Savant's Monty Hall problem by tilly
in thread Marilyn Vos Savant's Monty Hall problem by mutated

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