I've been thinking about the TIE interceptor recently, and how it interacts with the game's basic mechanics of hidden maneuver choice, all move + action, all shoot. The party piece of the TIE interceptor for a long time has been to PTL to both boost and barrel roll, letting it get into all sorts of tight spaces reactively. A few other ships have co-opted this ability: Engine Upgrade R2-D2 Corran Horn and Darth Vader. This is a very powerful ability against lower pilot skill as it gives anything that can double reposition a huge reactive ability.
X-Wing has alwaus had a bit of a PS problem. In Wave 1-3 pilot skill wasn't important enough: TIE interceptors were countered pretty hard by turrets in any form and the rest of the game didn't really care: other high PS pilots weren't worth the expense over generics unless you wanted a specific ability. The introduction of the TIE phantom in its original Super Interceptor form made pilot skill too important: you all but needed PS10 or another counter to avoid a very bad matchup.
After the phantom was errated to work differently we had a wave of the fallout from Wave 4: the two ship list. Since then the TIE interceptor and its fellow dodgers have received a lot of help from Autothrusters and Palpatine to survive the turrets, and now they themselves have taken the Throne of Unpopularity for being the new thing stamping on the generics and for many more importantly the non-repositioning eponymous T-65 X-wing.
What is effective arc?
Take a ship without repositional ability such as the X-wing. To kill an enemy of lower pilot skill, you have to predict where it's going to go and try to aim your firing arc at it. This is the core gameplay of X-wing. Against an enemy ship with higher pilot skill this is much the same: it'll shoot first but if you predict its move you'll get a shot at it.
Boost and Barrel Roll change this dynamic in interesting ways. I'm going to introduce a new term here, Effective Arc. This is the area your firing arc covers plus the area you can reposition to minus the area your opponent can reposition out of. We all know how valuable expanding the area you can shoot at is from turrets, and repositioning has much the same effect against lower pilot skill. It also has the effect of reducing the area lower pilot skill can shoot at you.
Against lower pilot skill a ship can can reposition has an expanded effective arc: it's got more freedom of maneuver choice as it can correct. Against higher pilot skill, a ship has a reduced effective arc against an enemy that can reposition. If you catch a TIE fighter in the edge of your arc it can barrel roll out of it, which effectively makes the arc in which you're certain of a shot smaller.
The larger the magnitude of this two effects, the harder it is for a lower PS opponent to get a shot at all as it has to aim its own arc and predict your maneuver much more tightly. Decloak + barrel roll was found to be much too strong: it warped the metagame towards Primary Weapon Turrets (which were then unaffected by Effective Arc as dodging them meant no shot on them). Nowadays it shifts the metagame towards high pilot skill: if you beat a repositioning ship on pilot skill boost and barrel roll just expand their possible ending positions: they can't dodge away if you predict their move correctly. This is how the phantom "nerf" works: Decloak no longer expands effective arc, it merely increases the board positions you can move to. That's a powerful effect but not as powerful as effective arc.
In a head on engagement, Boost gives you the biggest expansion of your effective arc as its ability to change angle makes the area you can cover very wide. This is why it's called the more aggressive of the two. Barrel Roll lets you sideslip and therefore gives you a smaller expansion of your effective arc but more ability to dodge out of the side of it, reducing enemey effective arc more.
The Boost-Barrel combination has a very large impact on effective arc: the area you can dodge out of and into is huge, and it's not too difficult to keep your own shot while dodging theirs. This gives the TIE interceptor + Vader and to an extent Corran a lot of strength against lower PS ships. Based on "Acewing" you could argue too much strength when combined with Palpathrusters's mitigation powers the few times it is caught.
This is why the TIE interceptor is addicted to PTL. If the TIE interceptor takes another EPT or if FFG were ever to rule Boost and Barrel Roll to be mutually exclusive a la Gonk (I think Acewing would have to get much worse before they do that) then the effective arc of the TIE interceptor decreases. It's forced to rely more on its dial: it becomes less Phantom Mk I and more Phantom Mk II. This makes EPTs other than PTL a bit more attractive on the mid skill pilots by unlocking those white maneuvers.
So how can we use effective arc to kill Soontir with lower pilot skill?
You kill an interceptor with focus fire, but the tiny size of your effective arc against it makes it very hard to do that.
Effective arc gives you a very hard time with a low pilot skill against an interceptor, but not an impossible one. What you need are maneuverable generics.
The two tactics against an arc dodger are to reduce its effective arc and to account for its effective arc.
Accounting for its arc means thinking in terms of the TIE interceptor's dial and its repositions. The easiest way to do this is to visualise your firing arc as smaller: consider areas it can dodge out of as not in arc at all when you anticipate its maneuver. Range 1 is pretty much a no go zone: it'll zip out of that no problem. The rest depends on angle. Take two range rulers, lay them down in front of a small base to see where its arc is and put a TIE interceptor in there: find the places it can and can't boost and barrel roll out of.
Your ability to account for effective arc is improved by your positional ability, which is dial plus any repositional actions you have. Knowing where to put your arc doesn't help you much if you can't put your arc there. And if you can't put your arc where it's going, it's probably safer not to try if you can by considering the other side of effective arc.
The TIE interceptor can get a shot on just about everything it wants with such a large effective arc of its own, but it has a blind spot: if stressed (and thus unable to K turn) it cannot fire at where it was. Place a small base on a table, then take another, hard 2 off of your starting position and try to barrel-boost yourself a shot. You can't do it. There's a trianglar blind spot right behind its starting position: go there and it can't get a shot at you.
Once you have a shot, there's a way to ruin that TIE interceptor's day: stress and ion. Ion doesn't influence effective arc but it tells you exactly where the interceptor is going. If you've got a good feel for effective arc you can then line up all your low PS guns on it without it being able to get away. Stress leaves it with its full dial to play with but costs it its actions, meaning effective arc is out of play for a round and your firing arc is its normal size. Better still, the two most useful stress effects (Flechette Torpedo and R3-A2) don't require you to hit. Lower PS Tactician is less useful: once you account for effective arc its chances are much smaller. It's more useful to think of Tactician's R2 band as a no go zone for the TIE interceptor: don't aim it where you think the interceptor will go but where you don't want it to go.
The TIE interceptor's actions can also be stripped by blocking. Again maximum maneuverability is at its most useful here for blocking that 2-turn. A blocked interceptor gets no actions, which means your firing arcs are at full effectiveness. This can aid your less maneuverable ships in getting a shot.
A Conner Net, if you can drop it, will both strip its actions this turn and ion it next turn. Plus it'll hit it for 1, meaning you only need to hit it twice rather than three times to kill it.
Edited by Blue Five