It could help you, but there are other ways to break plateaus.

Jump Squats on a smith should be done with light weight. Heavy weight compressing your back with each jump could land you with a serious back injury... trust me, thats the last thing you want. My back is f'ed and heavy squats are pretty much outta my game now. <img src="http://www.massmonsters.com/infopop/emoticons/icon_mad.gif" alt="Mad" width="15" height="15"><!--graemlin:--> as well as deads. I can't even do traditional deads... have to use a trapbar, which I do like a lot anyways.