She was right. It was not pain-free in the way that having six-inch nails driven into your head by a demented Viking is not pain-free.
Her words set me thinking (not at the time, though, as my mind was occupied with trying to keep still and not scream) about how and why we actually use these double negation constructions.
Here are some examples:
- The strategy is not entirely without risk
- The expedition was not risk-free
- His actions were not without consequence
- He is not an unpleasant person
- The atmosphere was not unwelcoming
- The atmosphere was not without tension
In other cases, however, it seems that we are doing precisely the opposite, namely heightening the positive statement by using a device that usually weakens it (an atmosphere that is "not without tension" could well be intended and understood to mean an atmosphere that was positively fractious).