Ok there is one thing I would like to add: None of these look anything like an RDL, I was given the opportunity to work with a pretty well known strength coach for a couple of days and the way that he explained it the bar will never get much lower than the knee. Basically you want the hamstrings and low back to be pre stressed so they are flexed the same way they would be for a squat, then pushed back till the hamstrings are fully pre stressed. The bar is lowered down while keeping contact with the thighs and the ass should be pushed back as you go down to accomodate for this. This is a good move for an olympic lifter b/c you are being redundant if you are doing sld, which is what the picture is depicting, or dimmel deadlifts. The olympic move I have used that mimics the dimmel is the stiff arm floor pull, sometimes snatch grip sometimes clean grip.