So if you want the grenades for your special you can change to it. I do this as well cause double grenades during radiance kicks ass. I like also like the survivability of it. Otherwise you're gonna have to try it out and see what you think.

I don't typically use double grenades. The burn attached to firebolt grenades will kill a full health enemy (ninja edit: not quite, but I usually get two grenade hits, which is a kill) if you use both touch of flame and viking funeral during your radiance; the added benefit of not needing line of site is too good to pass up as far as I'm concerned. It's a best when coupled with Praxic Fire.

I remember when I was first playing Halo: CE, one of the better players I knew taught me to make fine lateral adjustments when aiming by moving my character side-to-side, rather than looking. It's something I think we all do instinctively by now, but I'm always conscious of it because it was so specifically pointed out to me.

That said for your playstyle, that looks pretty vicious.