The X result gives really nice game moments. You remember the games well, which is part of the purpose I think. Look at all popular games, even thriving competition based games (that famous CCG is based on skill AND luck. Remember that too deck slam? Gaming history!)
That being said, I wish FFG was more creative in their dealing with the result. I actually dislike Deadly removing the result completely, making it from the best side of the die, to the worst.
What if Deadly was 'if an opponent rolls a dodge or 3 defense, he must change the die to another result of his choosing'
Or 'if opponent rolls a dodge, instead of preventing all damage, the attack deals half damage, rounded don't
Those abilities still make the dodge result desirable.
Just my 2 cents