There is no option for this. Consolidated actions are a PvP feature only.

I have a couple different points to make, so I'm going to post them separately so people can like like and notLike them separately.



In PvE, this could have some undesirable side effects for some jobs, in the vein of forcing certain "upgraded" actions when the "downgraded" action would actually be better.


To use RDM as an example, assume the following:

You are Verstone Ready.
You do not have Dualcast.
Your mana is 70|80.
You are mid-GCD after Dualcasting a spell.
Swiftcast is available.

Swiftcast→Veraero would get you to 81|80 in a single GCD, you would still be Verstone Ready, and you would be able to guarantee Verfire Ready by closing with Verflare.

If consolidated actions were in effect, you would be restricted to using Verstone→Veraero or Jolt→Veraero, taking two GCDs to do what should have been doable in one, and after the combo you would only be Verfire Ready.