> If I write code that needs a ['Jan', 'Feb', 'Mar' etc] type coord to work, then I need to check if the cube has a 'month' OR 'month_shortname' coord.

Sorry - I'm missing something. That coord could be called *anything* - not just "month" or "month_shortname". And that would still be true even if both default values were the same.

For what it's worth, I'd rather we didn't have two versions of the same function anyway!