it's true...I just don't know how you can go deep enough with out our trailing leg going down with you. People are not that different. That is unless they are seriously deformed. There are a lot of myths in the bodybuilding community on exercises. Some say that when doing squats your thigh should not go beyond parallel and that your knee should not go beyond your toes and so forth. Doing squats that way is border line impossible and will make you prone to injuries. The knee joint is most stable at the ends of its range of motion (fully extended and fully flexed). When the knee joint is at 50% of it's range it is most unstable (most prone to injury). Changeing direction when knee is at it's most unstable position with weights is an accident waiting to happen. The lower portion of the tear drop muscle also known as vastus medialis obliquus and it is responsible for keeping the patella and patellar tendon in the correct position in the center of the knee. The only way to exercise the VMO is to use full range of motion on leg exercises. Unless you use full range of motion you don't exercise VMO which might lead to problems down the line.