[Versus]

I believe it is correct.

If you use Stonstance, Whirlwind and Voiddance are locked out for a 4 minute cool down. If you use Voiddance or Whirlwind, the one that you didn't use and Stonestance are locked out for a 40 minute cool down.

It makes sense...Whirlwind/Voiddance are kind of "oh shit" disciplines that you're using to save your life...they should have a longer recharge. You get the benefit of using Stonestance every 4 minutes if you choose to just mitigate 90% of the damage instead of avoid all of it.