Steve Shaw: By the way, the word you were looking for was "insidious."

Nigel: I think Iains probably used the word he intended:

Steve: How do you know what he "probably" meant, and how will you ever know?

At least I included the comment that I think he probably meant to use the word he actually used. This was certainly less strident than your assertion that he used the wrong word.

As for 'how will you ever know?', I would imagine that we'll get clarification from Iains at some point. But even if he confirms that he always intended to use 'invidious' I doubt that that will be enough to convince you.