Ie, create a new thread, or multiple to execute code in parallel?

No thread control, but it supposedly can do async (promises). There are other ways to offload that I generally avoid.

NS does provide separate processing queues, and they are intended for breaking up work for parallel processing. Without any SuiteCloud Plus licenses, you get the ability to use two queues for free with a Map/Reduce script. With SC+, you get 5 queues per license (unfortunately, the first license only gives you three additional queues on top of the two free ones). The SC+ queues can also be used to run multiple scheduled script deployments in parallel.

Thank you for this information!