I think you'll find 'rigor' is the American spelling.

As to your defence of hijacking - I'm glad you find it fun to query the way people write as opposed to addressing the content of what they write (which was the thrust of my complaint on the other thread you mentioned). It's not my idea of fun, but each to their own.

I shall not be responding again as I am clearly breaking my own rules of rigorous adherence to the original topic (insert smiley of your choice, depending on whether or not you think I am to be taken entirely seriously).