This range, 50-75% of 1RM where maximum power is produced.
...
At weights heavier than this, velocity drops off to the point where power begins to diminish; remember, power requires high velocity. But at very light weights the velocity is so high than maximum recruitment of muscle is not possible.
...
So the load must be optimum for power production. Weights in the range of 50-75% are in the right range for weight training, for the speeds we use for total-body explosion.
As it turns out, the ability to produce force against a weight is dependent on the speed at which the movement is trained. What this means is that if heavy weights are lifted at a slow speed, the lifter gets good at lifting them at that slow speed. So slow deadlift training will not make the clean move faster.
...