Starting from this position:
If white plays c, the score is -3 (white points are treated as negative). If black plays c, the score is 0. So the current score in the bottom left is the sum of the scores divided by two, which is -3/2. A play by either player is worth the absolute value of the difference of the scores divided by two, which is also 3/2.
From this position, if white plays c, we know from the result above that the score will be -3/2. If black plays c, the score is 2. The current score in the area is the sum of the scores divided by two: 1/4. A play by either side is worth the absolute value of the difference of the scores divided by two: 7/4.
So, c is worth more than a but less than b. But because of tedomari, with black to move first black should play c, not b.
I've done these calculations in my head before, but never actually made the steps explicit like this. I think the steps are correct but I could be proven wrong
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