>You ideally want to take measures to reduce the likelihood of a given recipient seeing anyone else's copy and thus having a chance to spot the variance, but there are ways to do that
How, exactly? If you know someone else received what you believe to be the same document, what's the disincentive?
Is it mostly a matter of attempting to not give away any indication of who else may have received it, so that no one knows who could be a candidate to compare with? Or including some amount of explicitly-marked data specific to the recipient which they somehow would have difficulty censoring before sharing?
How, exactly? If you know someone else received what you believe to be the same document, what's the disincentive?
Is it mostly a matter of attempting to not give away any indication of who else may have received it, so that no one knows who could be a candidate to compare with? Or including some amount of explicitly-marked data specific to the recipient which they somehow would have difficulty censoring before sharing?