This is an amazing clean technique primer and speed developer for intermediate to advanced lifters. This exercise will develop confidence and speed under the bar, and will teach terminal full extension to a lifter in order to maximally recruit posterior chain and keep bar on a vertical force vector.
Block training is ideal for creating positional strength and awareness. Additionally, by starting from a static load at a determined phase of the clean; you can increase power production and teach athletes to finish the pull. Increased speed development under the bar is an additional expected outcome.
Lifts from the "tall" position specifically target your ability to finish you pull and get yourself under the barbel faster. Catching the barbell lower and quicker will allow you to increase your lifts since you will not be able to pull the barbell as high. By starting in this position, you limit the ability to throw your hips out front, which is a HUGE fault by many lifters. Focus on finishing your pull VERTICALLY instead of bouncing the barbell off the hips/thighs.
The muscle clean variation is perfect for pre-liminary work sets and engraining technique. By negating the ability to "reflex" under the barbell after the second pull, you will develop the motor mechanics of standing up VERTICALLY through the bar to finish the pull with the leg drive, and seamlessly progress into the high pull.