The issue I'm talking about is whether the voter is the person whose information is being used. I cannot see how this can be checked without individual verification, either before with ID, or after with confirmations. How would the voter registration data tell you this?

As for the claim, I believe the issue is that without the above checks, there's no possible way to know if that fraud is being committed in the first place, especially with at least 40% of the population abstaining. You're saying the measurement shows that it's rare while I'm asking how the measurement is even possible for this type of fraud. Is that the fundamental disagreement we have? If so then I guess this thread has run its course, but I do wish there was a way to agree.