Question on Tsgrinder and Hydra

[barcajax () gmail com]

I have been tasked with demonstrating how trivial it is to brute force a server running VNC and Terminal Services.
I have a wordlist that will be used by both tools.
Tried both GUI and CLI versions of Hydra by specifying the protocol (VNC), password file and IP. I have a problem as 
Hydra keeps prompting me to include the -l switch to include a username to brute force. VNC does not have a user so can 
someone please tell me what I'm missing in this picture?
I used Tsgrinder against Terminal Services and it worked like a charm. My only question is, does it have a switch to 
control brute force attempt timing like Hydra does? I don't see one.

---------------------------------------------------------------------------
This list is sponsored by: Norwich University

EARN A MASTER OF SCIENCE IN INFORMATION ASSURANCE - ONLINE
The NSA has designated Norwich University a center of Academic Excellence 
in Information Security. Our program offers unparalleled Infosec management 
education and the case study affords you unmatched consulting experience. 
Using interactive e-Learning technology, you can earn this esteemed degree, 
without disrupting your career or home life.

http://www.msia.norwich.edu/secfocus
---------------------------------------------------------------------------