Please speak more this.
Lifting explosively (eg: Ronnie Coleman) has been shown to have the potential to recruit more muscle fibers. By lifting a weight with a higher velocity, you increase the power put into the movement.
Most beginners use sloppy form to use heavier weight.
For example: Bicep curls, a beginner will use sloppy form so they can use more weight, but their biceps will receive less stimulation because other muscle groups are taking up more of the workload.
Same example: Jay Cutler will lift explosively, and look like his form is loose, but he is increasing the explosiveness of the movement, and actually hitting his biceps with more workload.
Think of the largest bodybuilders:
Ronnie
Jay
Branch
James
etc., etc
how many of them have been scolded for their "poor form" on various movements.
Another example is when Jay was getting flak for his "loose form" on pulldowns in a recent video on Flexonline. He was using explosiveness in the movement, but if you paid attention, he wasn't using momentum to move the weight, he was using his lats to increase the velocity of the movement.