Ghost Rider to the rescue! The season premiere got the highest delayed viewer rating in the show's history.
http://comicbook.com/2016/09/25/agents-of-shield-season-4-premiere-gets-huge-ratings-bump-from-d/
What these ratings seem to tell us is that the Agents of SHIELD faithful are willing to stick with the show, they’re just not willing to stay up past their bedtime. It will be interesting to see how the Live+7 ratings stack up to last season’s, and whether good word of mouth following Ghost Rider’s debut will draw even more viewers into Agents of SHIELD Season 4.
What it could tell us is that solid WOM got the less than faithful and those who had dropped the show to check it out. That's another theory.
Let's see what this weeks Live numbers are, see if that goes up. That might back this theory.