Apple Cinema Tools Inverse TK

For the life of me I can not get proper inverse TK on this clip. I tried several times, I selected a few different A frames, no luck.

Wait a minute... That little check box that you're supposed to leave selected...

Well, since my result is crap, I fall into the category "does not produce the correct result" don't I?

Let's try to uncheck the bugger...

And you know what? That was it! It works! Done clean, beautiful!

Why the misleading? Why oh, why?