Exactly, many large companies have a company policy that limits them to only confirm the dates and title at the company. Any further elaboration is prohibited (positive or negative) and a former colleague of my missus did get into trouble for elaborating positively in a proper reference when they had such a policy in place.

True, but there is an effective way around this:

"Would you hire Jack(ie) again?"

Tells you all you need to know.

What if the response is "No comment." as per corporate policy? I think a lot of people would interpret that answer to simply mean "no", but it doesn't necessarily mean anything regarding Jack(ie).