Edo Tensei can be 'ended' by the souls coming to peace?

To speak frankly, I think how Sai's resurrected brother, Shin, was 'defeated' was pretty lame. His soul got some sort of closure from seeing that Sai finished the infamous 'I have bonds too!" book....and then Edo tensei ended???? Lame.

Granted, we have very little info about Edo Tensei as a whole...so I won't be able to completely defend that it doesn't make sense......but it doesn't make sense to me and here's why...

I don't understand how the soul itself that is resurrected could have any bearing on the technique itself that the user performs [Kabuto in this case]. If Kabuto is the one binding the soul to the living world, then how can the soul itself release that 'binding'. Now, I would be much more understanding if Shin did a sealing tech (or anti-sealing tech) or any technique for that matter (ninjutsu, genjutsu), but alls he did was reach peace and then his soul was not bound. That brings up the assumption that anyone who is resurrected is not at peace....while that is possible, it is not very probable.

It's just a weird situation now that it's happened. Could it be prevented if Kabuto takes 'full control' of the zombies so they don't have a personality to reach closure??? What about people who died 'in peace'??? Did all of the people that Kabuto resurrected not have any sort of peace or closure when they died? Did all of them die unexpectedly in battle? Didn't any of them die from natural causes where they could have reached peace on their own? What about if they did die in battle, but reached peace before they died (like Jiraiya).

So now with all the rest of the zombie battles are we gonna have to see a bunch of sappy "closure" speeches and all the zombies reaching 'peace'??? I could handle that for a couple zombies, but all of them...yuck! That's gonna be a lot of sappy speeches in addition to all of Naruto's sappiness that will have to come up to 'bring peace to the ninja world'.

I just think this is a cheesy way to deal with the 'undefeatable' zombies that we thought would bring cool revelations and cool techniques to seal them....not sappy words and speeches (like the one Kankuro is having with Sasori).

Am I the only one that thinks this is gonna be superbly lame if all teh zombies are going to be defeated in this manor? I shouldn't jump to conclusions, but I'll be disappointed if all these bad-ass zombies are defeated by hugs-no-jutsu.