In SC, you want to grab on your opponent but you don't want your opponent to grab you. Unfortunately most of the time both you and your opponent can have grips on each other at the same time. The dancing game then start from there.
To avoid that, you have to "tear" apart your opponent's grips. After tearing, you will end with one grip on your opponent but your opponent has no grip on you, you can then move in and attack.
This is why the "tearing" principle can be used to counter the "shaking" principle. If you have no grips (or only 1 grip) on me, you can't shake me.