Turns out that in Apple Mail, the simple stuff eludes us “smart” IT types by being obscure.

After attaching an image in Mail, Apple sneaks a new menu at the bottom of the page where you can choose the image size.

See below for an example:

Once we had that changed back to a more reasonable default (Medium in this case), all was well in the land, and we both learned something new!

Notes for Apple (just in case someone’s listening):

I like the idea, but I think the implementation leaves something to be desired.  The UI for this is very non-intuitive, some kind of hinting wouldn’t go amiss here, or dare I say it, a total relocation of this to the top of the window with the other icons and menu options.