It seems you have other problems (crap infrastructure and no change control) to deal with before the issues in this article become your biggest concern, but are not the cases you list themselves partition problems?
They cause partition, but their origin isn't the network. Nobody who runs a large system has perfectly behaving infrastructure. Infrastructure always works better in a lab than in the real world. Even if you imagine your infrastructure is rock-solid, people often make assumptions, like their quota is infinite, or their application will scale past the theoretical limits of individual network segments, i/o bounding, etc.
The point is, resources cause problems, and the network is just one of many resources needed by the system. Other resources actually have more constraints on them than the network does. If a resource is constrained, it will impact availability in a highly-consistent model.
The author states that simply adding network redundancy would reduce partitions, and infrastructure problems are proof that this is very short-sighted. "You have bigger problems" - no kidding! Hence the weak-consistency model!
