This workflow, Imposed Plates, goes through Preflight, then imposes a 16 page booklet, and then moves a copy of that imposed PDF to another workflow called Imposed Proof just before pausing.
The pause is prior to making plates. The thing to do here is wait for proof approval. When you get it, release the job and it will continue to the plate making steps.
What does that other workflow do?
It turns out that it is simply an Export to a proofing system. Could you do that right from the same workflow? Sure. To do everything from a single workflow, put an Export (or a Direct Output Action if you are driving the proofer with our RIP) in the place of the Copy action the main workflow.
I will walk you through the reason why you might branch the proofing out to it's own workflow.
Here are the workflows, empty and waiting for jobs.
I am the CTP person. I drop it in to this main workflow and it goes up to the pause point. I'm done for now.
A copy of that plate job is made into the Proof queue.
A different person is in charge of minding the proofers. That person has their own queue of work and their own queue in this workflow. Jobs shows up here and they can re-order them, set up the printer, and print them whenever they are ready. Their work is separated out from mine and if they mess it up or delete it, the original is not affected.
Branching and linking workflows is a preference and can be a convenience for some work styles.
If you want to see some other ways to route things in the system, you can look at this: Routing with the Preflight Action