No, not your legs, but have heard if bending your front knee. You bend at the waist and you can bend your front knee...and if you can't draw to full draw while bent at the waist, you are WAY over bowed or don't have a clue how to properly draw a bow. Bending the knee will also work IF you can get the angle, and it was Ferguson that I believe stated that in a book....that's the 1st place I ever heard that.
Don't mean to be argumentative but bending at the waist has nothing to do with your alignment or draw length IF you know how to draw a bow correctly. Bending at the waist has nothing to do with the act of drawing a bow to proper alignment, nor does it make you short draw. I show this in detail in The BowHunters of TradGang.com DVD.
You can shoot from ALL SORTS of positions with proper alignment and good form and a consistent draw length.