This graph has me thinking Advanced turret gyros should be worth taking almost routinely.
I'm not seeing much effect of having turret gyros or not.
I took my 5-Conquest fleet (me in flagship Medusa, along with Gryphon as flanker) out and tried a couple of different variations against the 2-Ordos fleet. In all cases, the Conquests had Squall, Locust, Mjolnir, Gauss, HVD, Heavy Mauler, and 2 Harpoons. In each of these cases, the enemy fighters were removed (through modifying ship_data.csv to not have any fighter bays), and hulks were removed as soon as they appeared via repeatedly using the "removehulks" command whenever a ship died. Thus, the reasons for non-hits are misses (ship wasn't where the projectile was headed) and overkill (ship died while projectile was en route), and eliminating fighters and hulks as causes for missing.
The 3 cases were:
1. Without turret gyros. This means the Conquests had 29400 flux capacity each.
2. With turret gyros, which means the Conquests had 27400 instead of 29400 flux capacity (i.e. accounting for the fact that turret gyros take up OP).
3. With turret gyros built-in as a 4th s-mod, essentially getting the turret gyro hullmod for free (i.e. retaining 29400 flux capacity).
The results were as below:
No enemy fighters, remove hulks, no turret gyros (SS 4710)
shield armor hull hits fired hitrate time %squall weapon
150821 8460 18140 853 1560 54.68% 3.380 100.00% squall
47207 10106 52730 3027 5190 58.32% 2.566 75.92% locust
57825 36405 61989 588 747 78.71% 1.868 55.25% mjolnir
78687 13555 34173 247 352 70.17% 2.347 69.43% gauss
39575 3686 13451 287 353 81.30% 2.353 69.63% HVD
9820 19148 14378 330 456 72.37% 2.533 74.95% heavy mauler
38672 23994 51449 233 344 67.73% 0.860 25.44% harpoon
No enemy fighters, remove hulks, with turret gyros costing 10 OP (SS 4748)
shield armor hull hits fired hitrate time %squall weapon
188287 9449 16738 998 1762 56.64% 3.818 100.00% squall
47958 12082 60546 3369 5505 61.20% 2.722 71.30% locust
61259 36099 54801 584 697 83.79% 1.743 45.64% mjolnir
85253 14662 38267 265 386 68.65% 2.573 67.41% gauss
43385 3477 12934 279 337 82.79% 2.247 58.85% HVD
10601 18365 13007 334 441 75.74% 2.450 64.18% heavy mauler
23933 22877 42788 170 292 58.22% 0.730 19.12% harpoon
No enemy fighters, remove hulks, with turret gyros for free (SS 4824)
shield armor hull hits fired hitrate time %squall weapon
183502 10871 18071 994 1660 59.88% 3.597 100.00% squall
49771 10355 61249 3176 5358 59.28% 2.649 73.66% locust
64354 36178 61211 611 748 81.68% 1.870 51.99% mjolnir
84069 14829 43667 270 398 67.84% 2.653 73.77% gauss
46394 3473 14685 290 353 82.15% 2.353 65.43% HVD
8490 22312 16665 341 453 75.28% 2.517 69.97% heavy mauler
24686 13529 35082 154 264 58.33% 0.660 18.35% harpoon
Of note, I realized that in my past data, the reason why Locusts had such a high uptime was because I forgot to account for that they get +50% fire rate due to Missile Spec. I had that factor for the Squalls but not for the Locusts. (Found it weird that even without fighters around, Locusts still had way too high of an uptime.) So some of my past stats for the Locust are incorrect for the time and %squall values, both of which need to be multiplied by 2/3; but the rest are correct.
Note that these values above are *not* valid for the typical Ordos fight, since they're with enemy fighters and hulks removed, so the actual hit rate is lower. The Mjolnir seems to have improved by around 4%, the Gauss got worse by around 2%, the HVD improved by around 1%, and the Heavy Mauler improved by around 3% in terms of their hit rates. So overall, an average of around a 1.6% improvement when the base rate was around 76% hit rate -- so it's small enough that it's unclear if this is just due to random error, since I only ran these fights once each. That the Gauss actually got slightly worse for example might mean that it was "luckier" during the first fight compared to the other two.
So I don't really see taking the hullmod as making a meaningful improvement in this case.
The question then is what is the cause of the remaining misses. The Gauss has the highest projectile velocity out of all of them (1200, compared with 900 for Mjolnir, 1000 for HVD, and 900 for Heavy Mauler), plus no spread, so it should be the most accurate when fired. However, its hit rate is consistently lower than the others. The two biggest factors are its low turn rate and its chargeup. It's the only one here with a chargeup of 1 second before firing, whereas the other weapons have 0 chargeup delay. The reason why this is crucial is that when a weapon isn't firing, its turn rate is 5 times (I think) its normal turn rate. However, when it's firing
or when it's charging up to fire or during cooldown, its turn rate is what's given in weapon_data.csv. So the other weapons will have a very fast turn rate just before firing, so the shot will be reasonably accurate. After each shot, if the target has moved too far off-target, they'll simply stop firing and track at the 5x rate before firing again. This means that even the Hellbore, the slowest one of the bunch (other than Gauss) at 5 degrees per second, will be tracking at 25 degrees per second just before it fires. Most weapons will be tracking at 50 degrees per second or higher before they fire.
For the Gauss, it's different. When it thinks it's ready to fire, there'll be a 1-second delay while it's charging up, and it'll be tracking at 3 degrees per second during that time, before firing. So that 3 degrees per second is all the correction it gets during that 1 second delay to account for target movement and the firing ship turning. If a target is 1000 su away, that amounts to 52.4 su. So yeah unless the firing ship is helping the Gauss track a target, it's going to miss quite a bit.
To test for this, I did the above test again, with turret gyros for free (i.e. as the 4th built-in s-mod), but this time, I changed the Gauss's chargeup from 1 to 0 and chargedown from 1 to 2. So it still has a refire delay of 2 seconds, but now it fires right away and then cooldowns for 2 seconds, instead of charging up for a second beforehand then a second after. The result was:
No enemy fighters, remove hulks, with turret gyros for free, Gauss set to chargeup 0, chargedown 2 (SS 4863)
shield armor hull hits fired hitrate time %squall weapon
167454 9635 22689 954 1667 57.23% 3.612 100.00% squall
51496 10317 54776 3137 5460 57.45% 2.700 74.75% locust
55386 32846 56820 540 719 75.10% 1.798 49.77% mjolnir
103068 20057 41243 322 409 78.73% 2.727 75.49% gauss
38429 3629 11576 268 340 78.82% 2.267 62.76% HVD
9416 18399 13521 314 441 71.20% 2.450 67.83% heavy mauler
29587 16313 37348 177 284 62.32% 0.710 19.66% harpoon
The Gauss ended up having one of the best hit rates. So yeah, the chargeup is the reason why its hit rate is lower. Putting turret gyros on won't really help all that much; there's probably something better to do with that 10 OP (put into caps if nothing else).