You can’t argue with a rock, so you can’t stop a rock-solid commitment, even with your own rock-solid commitment. But you can solve the game given the commitments, with the outcome for each side. If this outcome is inferior to other possible commitments, then those other commitments should be used instead.
So, if the hero expects that his commitment to die will still result in villain making him die, this commitment is not a good idea and shouldn’t be made (for example, maybe the villain just wants to play the game). The tricky part is that if the hero expected his commitment to stop the villain, he still needs to dutifully die once the villain surprised him, to the extent this would be necessary to communicate the commitment to the villain prior to his decision, since it’s precisely this communicated model of behavior that was supposed to stop him.
You can’t argue with a rock, so you can’t stop a rock-solid commitment, even with your own rock-solid commitment. But you can solve the game given the commitments, with the outcome for each side. If this outcome is inferior to other possible commitments, then those other commitments should be used instead.
So, if the hero expects that his commitment to die will still result in villain making him die, this commitment is not a good idea and shouldn’t be made (for example, maybe the villain just wants to play the game). The tricky part is that if the hero expected his commitment to stop the villain, he still needs to dutifully die once the villain surprised him, to the extent this would be necessary to communicate the commitment to the villain prior to his decision, since it’s precisely this communicated model of behavior that was supposed to stop him.