This in turn litters your code with Core Data isms, and means that one can not simply make use of their model as a standard in-memory model.

Compare to SQLite, where one can simply open and commit a transaction synchronously on any thread.

And yes, you can still not use a persistent store manage context on multiple queues.

Please stop using the word thread and use the word queue :)

The difference is that the 'model' is what binds all of your code together. The constraints of Core Data therefor introduce tightly bound constraints on all your code.

> Please stop using the word thread and use the word queue :)

Why? Queues are M:N mapped to threads, so they are still threads. Additionally, not all work is always done on queues, especially when working with legacy APIs.