So I was reading through the 200 threads complaining about the annoyance of ships running away, and I decided that the 200 threads weren't enough and that I needed to add my own.

So why are retreats in Sins so annoying?  I thought about other RTS when I considered this question.  In most RTS, when someone decides to escape from a battle, this usually means that the slower units are abandoned, while the medium and fast units stand a decent chance of getting away intact.  On the other hand, the opponent can decide to give chase for as long as he wants too, and until the routed party reaches the base or significant reinforcement, they also stand a decent chance of destroying the escaping force.  On the escaper's side, he must determine how much force to sacrifice as diversion to cover the retreat, while on the pursuer's side, he must determine how far to give chase and risk entry into enemy territory or even an ambush.  These considerations are both fluid: both commander can alter their course at any time, making it tactically interesting.

While this is the same in principle in Sins, there are a few factors that significantly alter how this works.

Firstly, apart from the scouts and the capitals, the ship speed in Sins are relatively uniform, and there is not a lot of different possibilities on how to retreat and how to give chase.  And since a fleet tend to retreat all at once, it also becomes risky not to pursue in full strength.  As such you either order all of them to run/chase or none.

Secondly, even when there are stragglers left behind, shield mitigation means that they have a disproportional survivability against heavy enemy fire.  This is contradictory to the common sense that retreating force is at their most vulnerable.

Thirdly, since repair and shield regeneration is continuous, the lull before and after phase jump extend both the pursuer's and the retreat's health.  Slight as it may be, this definitely help the retreat much more than it helps the pursuer.

Lastly, due to the planets and phase lanes, the battlefield in Sins heavily segmented.  What this means is that on a retreat, there are a number of natural bottlenecks.  Whenever a retreating party reaches a phase lane, the pursuer must either give up the chase or make a commitment to continue the chase.  If he choose to give chase, he's commiting to spending the antimatter, losing 20 seconds or much longer of control over his fleet, and risking entry into a planet he probably has no intel about -- a very substantial commitment indeed.

Taken all at once, these factors strongly discourages pursuit and tips the balance heavily in the retreat's favor, and I think this is what makes retreats so frustrating to the pursuers.

But -- ahem, I think I'm already getting off my own topic here -- the last point is worth more discussion.  The great majority of strategy games work either on a "field" system, where forces move freely on the map, as in most RTS, or a "node" system, where forces hop between points, as in Risk and first generation Total War series.  Both of these systems are pretty intuitive.  In a node system, if you move an army into enemy territory, you expect to be confronted by the full force stationed there, so sneaking pass an enemy entrenchment is impossible.  But on a field system, if you manage to sneak an army right pass the enemy, everyone think you're uber l33t and nobody argues about it.  The thing with Sins is that it's a hybrid; and a very confusing hybrid.  So when a whole fleet phases to your heavily fortified planet, and then phases out to another adjacent planet without suffering heavy damage -- a very possible scenario -- you think WTF, the game is imbalanced

So what's my point, you ask?  Well I'm not sure if I had one.  It was just interesting to think about.  I'm not arguing for any specific changes to the game balance, but I think the Sins Enhancement mod's 20degree phase angle is a move in the right direction.  It might also be nice to have the gravity wells enlarged and the phase lanes shortened thus emulating the "field" more.  Alternatively we could also shrink the gravity wells and make phase charge up significantly longer, thus emulating the "node", but that's less fun IMO.