Thread: squaring mitered corners?

I just remembered seeing Eleanor Burns ironing a mitered corner, using the fusible to hold it in place, then using invisible thread to sew it down like you would an applique. That way it would not shift and since there's no stress on that seam like there is on clothing seams, it holds it really well.

Mitered borders and binding scare the **** out of me. Maybe some day I'll get brave enough to try them.