Sometimes it's helpful to consider a distributed system through the lens of "harvest vs yield" where harvest is the proportion of information in a system reflected by a response, and yield which is the probability of receiving a response at all.
https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.24...
Now I know it is Eric Brewer himself who wrote that announcement. So I make no claim disproving him or knowing better than, I am just struggling to understand the implications. That CA terms has caused a lot of confusion (at least to me) and so far from what I have read talking about CA systems doesn't make sense.
Never heard of harvest & yield that's an interesting perspective. Thanks for the link, I'll need to go and ponder that for a while. It seems to take a probabilistic approach to these constraints.
But even in that article the description of CA systems is confusing. They describe it it means system can work only in the absence of a partitions. Ok, but then what does it do in the case of partition? The system will presumably do something accept requests, refuse to reply, ... I don't see how it can be both C and A though. That is why I equate that choice with a statement of "I believe partitions will never happen", which I personally think is not realistic.
We know that we can't have 100% harvest and 100% yield in the presence of partitions. We can play with different things though to shape the curve of these things as conditions worsen, however