@nyrath @Hcobb @isaackuo @MeiLin Actually, while I contemplate cancer analogies for growth-for-growth's sake, it occurs to me that there are obvious modes of failure that apply to tumors which also apply to GFGS civilizations.
Necrosis, in which logistic problems starve the center; and cancer-gets-cancer, in which attacking your neighbors to expand into their territory provides better returns than trying to expand into the now-distant margin of the tumor/sphere.
@nyrath @Hcobb @isaackuo @MeiLin
Applying the same principles to growth-obsessed societies/peoples suggest to me that GFGS civs are acutely vulnerable to breaking down into civil resource wars - and, if you're using relativistic transports, probably the kind of civil resource wars that leave nothing behind except the Cancer Emulation Is Not A Viable Strategy Memorial Stellar Graveyard of 3162.
@nyrath @Hcobb @isaackuo @MeiLin
(You can patch this with some notions like "every colony sends out n expeditions of its own then suddenly gets permabored with the whole idea of expansion", but like you say, it only takes one defector to blow up the whole thing.)