Setting the die as a two is the same thing as being told at least one of the two dice under the cup is a two. Why is that so difficult for you to understand?

There are only two friggin' dice. Just use your imagination. If you're told at least one of them is a two pick a die and make it two. It doesn't change. That leaves the other die in the two dice problem to be your variable. That other friggin' die has six sides.

No one said you had to combine the six sides on both dice and there is no reason to combine the sides on both dice WHEN ONE OF THEM is a 2. And if BOTH happen to be a 2, the solution to the problem is still the same: you pick ONE of the dice and count how many friggin' sides it has.

Geesh.