Electronic polling - how accurate?

An email this morning reminded me of the controversy over electronic polling. Frankly, I liked it. In our "wired" age, it makes sense.

But what if it's not accurate?

The machines seem to work properly at the beginning time of use. After several hours, though, - after they have heated up - tallies are not correct.

Now, this would not have been a problem during the March Primary in Woodstock - at least, at the polling place at which I was serving. There was not one electronic vote. It not only wasn't encouraged; it was discouraged. But not for this reason.

There must be a lot written about this. You can start here