In The Force Awakens, why were X-Wings so much more accurate than TIE fighters?

Question

In The Force Awakens, we see two instances of starfighters shooting at ground targets. On Jakku, two TIEs try and fail to shoot the fleeing Finn and Rey. On Takadona, Poe Dameron shoots the stormtroopers guarding Han, Chewie, and Finn as he flies by.

Why was Poe's shot so much more accurate than the TIE's?

Was it purely pilot skill? This shouldn't be a factor, because of the advanced targeting computer systems and the extensive amount of training both pilots have received.

Was it because the TIE pilots were trying to hit moving targets? This is closer to correct, but it seems like the TIE's targeting systems, being designed for high-velocity space combat, should be able to account for this as well.

So what was the difference between the two? Why were the TIEs not even able to get Finn and Rey within the blast radii of their shots, while Poe was able to shoot at least one stormtrooper directly in the breastplate while engaged in an aerial battle?

Answer 1

Poe Dameron does possess exceptional skill above and beyond most pilots, veteran or otherwise, who aren't Force sensitive:

"Captain Kun is an exceptional pilot, without question, as is Captain Arana, for that matter. But it's a rare pilot who engages one frigate and two Star Destroyers and lives to tell the tale." - Leia Organa (Before the Awakening)

To my own memory, the last time I've seen such a thing happen, that particular fighter was in the hands of a Skywalker.

Additionally, Star Wars Battlefront is considered canon, and if you refer to the technical specs of fighter craft in-game, targeting computers can only lock on to flying targets like other fighters & transport ships but not ground targets like walkers nor infantry. There's also a limited range, takes time to zero in, and can only be sustained for as long as the target remains within the crosshairs. Even against flying targets, the targeting computer cannot anticipate the target's future position at the point of impact, and fires only towards the target's position at the point of firing, so when shooting at a target moving sideways from the shooter's perspective, it is better not to lock on and just manually lead the shot on his own - and that's where skill and experience comes in.

Which makes sense - infantry are often too small for fighters, coming in rapidly from large distances, to paint as a target accurately enough, let alone discerning between friend and foe. Most likely, a fighter pilot shooting at ground targets truly has nothing but his own eyes, experience and skill to count on - that's why Poe is so much better at it. He wins on the skill check.