Someone has a sense of humor comes to mind, first. You’re suspicious as well, I can see that.
Hillary puts Nothing in writing. Never has. A lawyer thing, maybe, or just an act too stupid for words.
She is a lot craftier than to have created and sent that example. Anyone who has left a circle of arkancides/hits stacked ten deep around her and scammed, skimmed or laundered millions (if not billions) of dollars is not going to send BHO such a chatty warning note.
Yep, I call fake.
And for it to be in the letter form with a proper salutation is just too over the top.