Unbound stop root server lookup

[Guevara, Daniel]

Hoping someone can help me understand the root.hints functionality. 

From my previous email:
"I was under the impression that I could create a custom root.hints. For example the one you linked has 13 root servers. I tried configuring it with only one of those root servers, allowing outbound access to that server, yet the startup time is still not as quick as when I allow all outbound access. This leads me to believe that it is still trying root servers I did not define? (This was only a test and I am not proposing to only use one root server)"

Is there a way to do root server lookup on only the server specified (if it cannot be disabled completely)?