TinMan3rail posted:The procedure I suggest is wire the black and white wires first, then plug the transformer in and scratch the green wire on the outside plate of the transformer. If there is any spark at all, I strongly advise you to scrap the transformer
This right there says all you need to know - a true professional would not recommend nor boast about performing a continuity test in such a fashion at line voltage. As such, recommend that others, as I, to treat any recommendations or conclusions as suspect.