I disagree, Renault wouldn't let emotions hinder any on-track testing of 2016 components. They need to make advances for their own good.
I think it's as simple as the incompetence that got them into trouble, keeps them in trouble.
It has been weeks since they gave the green light for the upgrades at Austin. It's shocking they now need to hold back on parts of the new package. Not only do they need to test these items for next year, they also need to show the world that progress is being made, and get out of the negative spotlight they got themselves in.