Not punishable, just a dick move. I believe the plan is to eliminate this exploit whenever the devs have time to improve the trade system.
We're adding a 5 second timer at the end of each trade to give people a chance to review the trade before it going through. People won't be able to edit their offer during this time. It'll be out sometime in the next couple of days!
He can be banned for that to be honest. If it was successful and if it was done on a continuous amount of times, yes, get him outta here.
Zuclas its not bannable since its considered as scamming. I think you are right he should be banned for this but he wont so dont mind it :S
By fully reset, you mean just his stats? Or along with his house, permits, backpack, enderchest, etc.