NXT Drawing Test

Since it seems like WWE are going to continue sending main roster talent down to NXT, why not send one or two down a week and advertise them in advance? It’s really hard to tell who moves numbers on the main roster, but seeing who spikes a rating for NXT could be useful info on who they need to push. Plus it would presumably raise the NXT ratings. Or are they worried they don’t have anyone that can raise NXT ratings and they’ll be exposed for having no stars worth promoting in advance?
I think once we get through Survivor Series, they'll lose interest and NXT will be back to being isolationist again.