A few tests show: The helper is launched, processes jobs, but as soon as you return “” from JobRequested, it will terminate.
See also feedback case 62409 Add events to worker for Helper App open/close.
(currently only visible to testers, but should go public)
So you could keep your helper app alive for a while if you wanted.
You plan to feed it with dummy jobs, which just waste time?
I would be happy if there is the option with a timeout to keep them waiting efficiently (with <1% CPU usage) for newer jobs to make it faster when newer jobs need to be processed.
Sure. Definitely better ways to do it but you could keep the Worker alive if you felt it helped.