[Actualy, acording to the numbers your Astro-Creep is about to die by Carrot's hands (you cannot attack in defence mode, so I must assume you switched him to attack mode which means it's his ATK vs carrots ATK, that's 1900 vs 2200).
I'll therefore wait for you to either take back that attack, pull an ace from your sleave, or let your creep die.]
As for the new rule, it's definatly a go. I was thinking along those lines as well.
Here's a link to the battle phase rules, if you want. We don't need to go by all these rules, but they are the basis:
http://www.upperdeckentertainment.com/yugioh/train4.asp
You can ignore the structure of the phase, but check the "Detemining Damage" part.