What is interesting is that out of the six possible scenarios, three result in winning and three result in losing, which supports the 50/50 solution.

Nope.

Say you picked door #1 and another door is opened with nada behind it.

For the first three games, you choose #1 and "switch" each time, for the second three games, you choose #1 and "stay" each time, and the host always opens a loser.

Here are the results.


Switch each time:


GAME 1: PRIZE NADA NADA ~ Switch and you lose.

GAME 2: NADA PRIZE NADA ~ Switch and you win.

GAME 3: NADA NADA PRIZE ~ Switch and you win.

............................................................


Stay each time:


GAME 4: PRIZE NADA NADA ~ Stay and you win.

GAME 5: NADA PRIZE NADA ~ Stay and you lose.

GAME 6: NADA NADA PRIZE ~ Stay and you lose.

When you switch, you win 2/3 of the time and lose 1/3, but when you don't switch, you only win 1/3 of the time and lose 2/3.