Quick question regarding stunted growth

Sorry if this been covered but I am in a hurry and dont have time to search.

If a plant growing hydro has nutrient burn and the growth been stunted but the roots are still growing very well and look very healthy will the plant recover??

I guess I am asking can/should you visually judge your plant by the leaves or the roots..............thanks for any help

Yea I know you can tell everything from looking at the plant. When I get home I will post a pic to better describe what I am asking.