The Taurus I is designed to have 653-720 MGs active against incoming missile swarms. The low end is in the nose arc which has 5(Taurus I) + 12x54(dedicated Crestbreaker smallcraft) = 653 MGs. Other arcs have 60(Taurus I)+12(Tick)+12x54(Crestbreaker) = 720 MGs. The obvious thing to do is to test a Taurus I vs. a Walkurie, but I don't see a good way to make that happen :)
Dedicated smallcraft have two significant drawbacks----they are expensive (which certainly matters to the TC) and they are vulnerable to direct attack by ASF. The advantage is that they are low mass (which also matters to the TC), they can be pointed, and they may allow for a somewhat greater depth of defenses.
The ASF fighter doctrine against Warships for the TC is simple: close to point blank range and fire the missiles en masse. This likely will incur some fighter losses, but the odds of a hit are higher the less time there is for point defense to be active and there is a secondary goal of saturating defenses for the boarding parties.
Yeah, I think the ASF operators are going to go with a 'wait till you see the whites of your eyes' doctrine, given those numbers.
RE Small Craft as Point Defense - in this instance, the small craft would essentially be serving as independent turrets that dont strain the motherships fire control, can manuver with it, and can always bear on the incoming strike. Given 'always bear' and that the current results assume only 1/4 of the ships point defense is in arc, this suggests that a single Machine Gun on a single Small Craft shoots down, in current conditions, between 2 and 6 Capital Missiles.
Its trivially easy to put 12 MGs on a largish small craft, while leaving it able to still do its other jobs. By math above, thats 24-72! missiles killed by that small craft. Expensive? By that math, 30 small craft can squash the launch of one Walkurie. On a bad day.
And the same small craft easily mount more proper firepower than an ASF, and more armor. Sure, its less mobile.. but its only trying to be as mobile as the ship it is guarding, and is present in numbers sufficient that dogfighting isnt really an issue - your fighter is going to be in front of SOMEONES Small Craft Turret, and every small craft turret will have SOMEONE in its gunsights.
This is, obviously, an absurd result. Perhaps something else is going on here.
Proposition:
We may have erred in treating '720 missiles launch, 120 hit' as being a case of '600 are shot down'. It could easily be the case that '720 missiles launch, 160 make a successful to-hit roll, 40 are shot down, 120 hit'. This allows some value to even a small amount of PDS, makes missiles somewhat less of a 'overwhelming numbers overwhelm overwhelmingly' issue, and at the same time prevents big PDS belts from making missiles a nonexistent weapon system. If we model PDS as 'look-shoot', further, a certain % of missiles will ALWAYS get through - because the defenders would be allocating MG fire all at once, then starting to roll to hit, and unable to reengage any missile that survived its first x attackers.
If we treat it as 'look-shoot-look-shoot-look-shoot' ad infinitium (as is suggested by a X MGs always kill between 1/2 X and 1.5X missiles), then its strictly linear, with the defender having infinite reaction time and perspicacity.
Or perhaps the GM is already considering to-hit rolls, and failed to-hit rolls may reflect some version of damaged/deflected/shot down, again overcome by closing to point blank range.
Ballpark proposition:
1MG, in arc, fires 1 Time at 1 Missile. It has a percentage, 50% in our example (and I feel this is likely too high by at least half - 25% for a MG, and 50% for a future AMS seems better) of causing a kill.
Let X be the number of incoming missiles that have successfully rolled to hit (we will assume that point defense controllers are good enough to not engage probable misses). Let Y be the number of point defense mounts.
If X>Y, then obviously Y mounts engage Y missiles, killing half of them, and leaving the target struck by (X-.5Y) missiles.
If Y>X, then each missile may have more than one mount engaging it. For Y=2X, then you have 2 mounts firing on each missile. Each has a 50% chance of a kill. Two mounts would collectively have a 75% chance of a kill. Therefore, 1 in 4 missiles survive the run through the point defense. At something extreme, like '8 MG in arc for each missile), that number drops precipitously, to 1/256, or less than half of a percent. Yeah.. looks like 50% for a MG is way too high.
One advantage for this paradigm... once youve got PDS mounts in arc equal to the incoming probable hits, each further one is worth less. If you have to pre-spot all your fire, then some PDS mounts are going to be wasted shooting at dead missiles - and you hit diminishing returns/negative feedback. This way you dont overkill small salvos as hard, and have less impetus to go crazy on mounts entirely.
Finally, given that maaaasssive weight is paid for fire control on ship mounted massive-PDS belts, and NOT paid by fighters or small craft, suggest that fighters and small craft be at massively reduced effectiveness when pretending to be PDS belts. Not ineffective, but the warship is getting something for those thousands of tons of fire control.
Further note: current examples are allowing all PDS on all defenders to fire. It seems likely that ship A will recieve little to no protection against missiles targeting it from PDS mounts on ship B. Even carried small craft will be off-bore to an incoming missile, which would seem to greatly increase the difficulty of an intercept (this condition obtains less if the goalkeepers can place themselves at rest relative to an unmanuvering target and along the incoming attack bearing - but shutting off ones manuver drives to maximize point defense would at the same time seem to have bad implications in terms of number of missiles that would be on target to hit you.)
Final Note: We are really only having this conversation because of the potential of massive salvo model missile fire, made possible by either fighter carriage or by large numbers of launchers with limited ammo. Outside of such conditions, missiles are a poor weapon system best defeated by the same armor that also works against NACs.