HP : 3920
Attack Rating : 6105~
On this setup the head is 10.9 (Dust of the Black Pharaoh) with Woodcutter's Wrath (10.9 AR piece), the rest of the Attack rating pieces are QL11.
Now with a two purple Vigour (+494 HP per signet) dps setup, a level 5 Accurate augment (+150 AR), a pure anima HP (+940 HP) and all pieces as QL11 Attack Rating (except Dust and Woodcutter), you get the following :
HP : 3998
Attack Rating : 6257
So let us see here, you gain 152 more AR and 78 more HP with a double Vigour setup than you would with a double Violence setup, given the mechanisms of Attack Rating returns past 5200~+, it is a more interesting choice if you want to gain more damage while still meeting a safe HP threshold for NM raids.
So no, not a waste, far from it, although i agree if you run pve content (most of the NM dungeons) other than NM raids violences will be better (even then Vigour can have some small uses in there depending on the random groups you can potentially run with).
I invite you to calculate this yourself, unless you have potentially something else that can increase AR that i forgot that works only with Violence, somehow.