That Cheerful "Think Again!"

I have always found the rhetorical device of stating some misapprehension supposedly existing among their audience and then saying or writing "Think again!" at the end exceedingly obnoxious.

There is not only an often unwarranted assumption that the audience is thinking the thing they will presume to show to be false because they know so much more than the idiots in the audience do (especially offensive when the misapprehension in question is something only the deeply ignorant or profoundly stupid are likely to believe), but the cheery self-satisfaction in slapping them in the face with their presumed misapprehension with that "Think again!"

"Think that eating a tub of fried lard every day is good for your health? Think again!"

Think that's good writing?

Think again!