Status: IN
Observer and Mediator represent a fundamental architectural tradeoff between distributed and centralized communication: Observer distributes via subscription for maximum reusability but risks unexpected update cascades, while Mediator centralizes via a hub for comprehensibility but risks monolithic growth — making the choice between them a decision about which liability is more tolerable.
Two base beliefs on the relationship + one liability each combine into a unified architectural tradeoff
Depends on (SL): mediator-centralizes-observer-distributes, observers-more-reusable-than-mediators, gof-observer-unexpected-updates-liability, gof-mediator-centralizes-control-tradeoff