As long as you totally watch this 14 minute video explaining everything. If you don't? Good luck sorting through all that Grimoire nonsense.
A confession: I have literally no idea what's going on in Destiny. I also had no clue what was going on in Halo since about halfway through the second game, but I loved it all the same. Bungie, to my mind, have never been master story tellers. They are masters at making it rewarding as all hell to shoot things, so I tend to focus on that stuff: the shooting of things with the multiple different guns and whatnot.
Still, like Vaati's videos on Dark Souls, sometimes it's valuable to get some insight into why you're doing all this shooting, and who you are shooting at. Sometimes it's kinda cool to get access to insights you might otherwise have ignored.
I guess that's what this video is. It's Destiny for dummies. Or those who just don't really care all that much. Either way, it's worth a watch.