Huh, the CSG reference was perfectly clear to me.
To simplify, perhaps throwing out some key details while doing so:
The idea was that instead of spawning something like a Core Guard Post on just the homeworld, that -one- CGP spawns on multiple core worlds. If you manage to take out that CGP on a core world, it goes 'pop' on all the other worlds.
While the probability of having an overlapping field of fire death trap goes up, so to does the idea of having a place where they don't overlap. You could still go straight for the homeworld, but if one post proves impossible, then you could hit a core world and destroy it's counterpart and they all (for that AI at least) go up in smoke.
It's not my idea, so I'll let LT elaborate if necessary, but does that clear things up, chemical art?
It's not the concept of provided invulnerability the suggestion revolves around, but the 'take one down, they all go down' trait of the lower CSGS that it revolves around.
I've got a few thoughts on potential 'too easy' and potential counters to 'too easy', but I'm dead tired. If the idea gets discussed some more I'll elaborate.
I could imagine one brutal pick spawning only on the homeworld, a second brutal pick spawning on the HW and a third of the Core Worlds, a Core Guard Post (and clones) spawning only on Core Worlds, I could imagine the whole defense structure collapsing to easiness without planetary Tachyon, I could see a grab-bag approach actually allowing for an additonal brutal pick or two thanks to multiple avenues of taking the thing down. I could see Champions running away with things, I could see it breaking the 'strength check' we so desperately introduced to counter all those 10/10ers, I could see it making a nightmare out of a snake map or even a less linear one that has odds of spawning something in the center somehow. I could even imagine a Fallen Spire Shard Retrieval, Dire Guardian Lair, Spire Archive, or awkwardly placed Co-Processor being made exceptionally difficult.
I like the idea for being interesting to think about... I'm too tired to actually draw conclusions however.