The operating system, Win7, can, and does, run separate processes in the other cores. Some of the activity that you see in other cores is background routines unrelated to SS.
You do benefit from multiple cores in that these processes would otherwise be sharing the single CPU core with SS and degrading performance.
Much of the trouble experienced by folks with higher-end systems may simply be too many background processes that they are not aware of. Many programs install processes that run even when that program is not running.
There may be some pieces of SS, external to QuestViewer that the OS recognizes as separate processes that it can assign to another core.
An in-depth discussion of the subject by VSTEP might be helpful, or would have been earlier in the day.
I do understand their reluctance to say anything, given the compulsion of some to find a way to twist everything they say into a negative light.
