I wonder if we are all talking about the same tests. I had it done 3 times (to measure progress if any), and while it didn't really hurt badly - compared to the PN itself - it did involve sticking needles into my leg. Second time there was even a little bit of blood, which is how I know it was needles and not just a sensor. I'm assuming he was trying to get as close to the nerve as possible and then measure the conductivity lower in the feet.

That said, I'm not convinced an EMG changes much to the diagnose. In my case the larger nerves (sural) were damaged, so he could easily measure it, but in some cases when it's just the small fibres an EMG will not necessarily pick it up (if at all).

In any case, it will not make the cause (or causes) any clearer. But if alcohol was ever involved, it's a fair bet that it's the cause or part of the cause.