You might try to set the example. You claim to have this knowledge, why doesn't it NOW compel you to turn the other cheek? You've claimed from the beginning that once people have this knowledge that's how they'll behave, but it's not how you behave. Do you not see that this shows Lessans' view of human nature is hopelessly naive? It's simply not reasonable to believe that in the new world people will never get frustrated or exasperated or angry or hurt enough to lash out at anyone, you can't even do it in this virtual world.
There's no way to resolve this discussion. All we can do is stop, no other resolution is possible. A key part of Lessan's thesis is that anyone who understands it will be compelled to agree with it. Peacegirl thinks that's true. Nobody else does, so according to the book--and peacegirl of course--that means we don't understand it. If we did, we'd agree. Either we accept his thesis, or we don't understand it, there are no other options, and in particular there's no possibility he could be wrong. Once we do understand it, all our criticisms of it will go away. That's what the book says, and that's really all peacegirl keeps saying. Over and over and over and over... No defence or further explanation is necessary, all that's required is repetition, until we finally get it.