Q: What are masterwork rolls?
A: Most legendary weapons are capable of being Masterworked. The masterwork system is a way for you to upgrade your favorite weapons to their maximum potential.
Q: What does it take to upgrade a weapon to a masterwork?
A: Upgrading your weapons, in broad terms, takes a small amount of glimmer, legendary shards, and, most importantly, Enhancement Cores.
Depending on what Tier your weapon is at, the requirements to raise it to the next tier increase the closer the weapon is to being fully masterworked (Tier 10).
Q: What benefits do I get for masterworking a weapon?
A: Each tier that you increase your weapon will grant a small buff to a single stat, chosen randomly when the item drops.
Beyond that, at Tier 5 you gain access to a kill tracker. At Tier 10, your multi-kills will generate orbs of light.
Q: So what are these "masterwork roll" stats?
A: These are the possible stats that upgrading your weapon will grant a bonus to. Depending on what tier you are at, you can grant anywhere from 1-10 additional points in any of the stats listed to your weapon.
Q: Any catch with this?
A: The Bungie API currently says that all weapons can potentially roll with all stats as their masterwork stat. This obviously isn't accurate, as Blast Radius isn't applicable to, say, Auto Rifles.
The list you see on this page is trimmed to only show stats that actually appear on the weapon. However, it is possible that Bungie has additional logic behind the scenes that further filters these
possibilities to, for example, prevent certain items from being able to have an Impact masterwork. Until Bungie modifies the API files to 100% accurately display which masterwork stats are possible on
each item, take what you see here with a pinch of salt.
This perk's reliability is already self-evident, being like an inverted, quick-and-dirty Dynamic Sway or Zen Moment, making the weapon immediately start out more stable and accurate for a short burst instead of becoming so over time with sustained fire. With SMG's, especially the very rapid Lightweight family of SMG's, this perk turns them into a near-recoilless laser pointer for that half-second; the faster-firing the weapon archetype, the more bullets you can output before that bonus wears off. Useful thing to remember is that the perk's bonus resets the instant you stop firing, meaning you can proc it continuously by feathering the trigger - however, you shouldn't outright tap-fire like your gun is semiautomatic, since even if you use your scroll wheel, automatic weapons will shoot slower that way. Again, if you catch an unaware opponent in the Crucible, feather it; give them a quick burst, and if they survive, give them another.
Speaking of the Crucible, my only real problem with this perk (besides power creep - it's a *Season 1* non-damage trait) is that it's restricted a little too hard to the Crucible. There is absolutely no reason to use this in any PvE activity aside from maybe, like, a gun in Gambit you want to be good at killing adds *and* players without having to switch to another; even traits like Zen Moment or Dynamic Sway are useful for sustained-damage situations, and Moving Target can be combined with on-headshot(-kill) traits to make activating them more easy. If Tap the Trigger did *anything* tangible in PvE, this review would be four stars.
Also the "increases trigger sensitivity on digital-trigger controllers" is a funny detail I hope they never get rid of. It's cute.