My opinion is that it's to late for NAP to go back and think about a possible response. He agreed on resolving his opponent's spell by moving the card from the battlefield toward the graveyard. He had all the time he needed to think about a response before starting to move the enchantment.
Moreover, I think that what AP said (“it is now a 1/2 with 2 damage, so it should die”) it's kind of information NAP gained by his opponent due to his reaction. I don't think it would be fair to let him go back on his decision. :)
My two cents.

Them, in multiple blockers creatures… the standard way to assign the damage of the attacker its lethal damage to the 1st and rest damage to the next???

I feel that sometimes a player will give information to their opponent
prematurely and then be educated about that fact when we tell them to wait
with information before it's clear what's going on :).

If that is the case in this instance I'm not so sure. Mostly had to be
there.
Den 11 maj 2016 10:27 skrev “Jacopo Strati” <

Originally posted by Jacopo Strati:

Moreover, I think that what AP said (“it is now a 1/2 with 2 damage, so it should die”)

Just for clarity, he didn't actually say that. He only pointed at the creature, meaning that.

Excuse me if I address again the “how did AP assign damage in the first place?” issue.

I found an {O} answer:

http://apps.magicjudges.org/forum/topic/1631/

Edited Francesco Scialpi (May 20, 2016 08:29:01 AM)