I'm far from a pro but I'll weigh in – mostly because I want to be corrected if my view on balancing your range is way off base.

Your example is fine but tournament poker is so much more of a pre-flop game so that's where it really applies.

Balancing your range = not only 3-betting with premiums so that your big hands get action. If you polarize your 3-bet range to JJ+, AQs, and AK a thinking player is never giving you action unless they have you smashed.

A balanced range can be something like premium hands, the top of your folding range aka hands that seem pretty good but not good enough to just call a raise with, and some mixed in total bullshit like J6s.

Personally I like when I hold a blocker card such as an Ace or King because it makes it less likely that the initial raiser holds one. So a hand like A4s with a blocker, flush potential, and wheel potential looks like a very nice hand to me when I decide to mix it up. You can even use a hand like this for an uninvested 4 bet against an active raiser and active caller and you'll get turbo folds a ton but you need to know that spot…

If you want to visualize this concept, watch the Big Dog series while Dipthrong has position on him. That's a balanced range. You can never put Dipthrong on a hand and this is the same thing you want to accomplish at the tables. He does a combination of 3 betting and flatting to outplay his opponent post-flop in position.

Hagbard Celine said:  

in fact, in MTTs–esp the smaller stakes–having a polarized 3betting range is probably optimal because your opponents are never going to exploit it by raise/folding TT/AQ or 4betting you light.

 +1 – too many stations for balance to matter.