One of the biggest moments that defined the Freespace universe was the destruction of Capella by the Sathanas fleet, we all wondered what would happen after that, if the GTVA would fight the Shivans again or find a way back to Earth and numerous campaigns were made to answer that question. But have anyone wondered what if that event was averted?
What would happen if the Sathanas fleet was destroyed? Be it by a weapon deployed by the GTVA (or them actually deploying their ships behind the Sathanas :

), by something going very wrong on what the Shivans were trying to do or by the hands of Axem's Barney (most propable reason

). What do you people think would happen if those 80 Sathanas were destroyed at Capella?
How the Shivans would be affected is already a huge question by itself, they lose a huge part of their fleet (possibly trowing their forces into a great confusion) but they still have more than enough forces to keep the attack and overrun the system (we see this as its said in the game that the Shivans keep pouring out of the portal non stop in one of the briefings), so their choices would be:
a) Keep the attack and invade the main GTVA systems.
b) Hold position and wait for more Sathanas to complete the original objective whatever it was.
c) Retreat, seeing that resistance is too high or that their ''experiment'' (or whatever it was) failed.
The GTVA, on the other hand, would see this as huge morale booster (specially if they did it) and would earn a brief respite seeing that the main threat just vanished (a huge part of the small craft the Shivans deployed must've come from the Sathanas) but they also took serious losses to their fleet in system and the evacuation would still need to be completed, also if the Shivans were trowed into disarray after that they would counter attacks immediately (possibly crippling to the remaining Shivan forces), either way so their choices would be:
a) Keep the original plan (blowing up the nodes) but delay it somewhat so that everyone can get out.
b) Abort the original plan and hold position, defending the node and wait for reinforcements.
c) Launch a counter attack and try to break the remaining Shivans forces once and for all, only stopping at the nebula (at most launching scouts beyond the 2nd Knossos).
A last thing, its been a while since I played the main FS2 campaign so I'm sorry for any mistakes there might be.