What are the settings on your Canon XLH1? Are you coming out of the HD-SDI port in the back?
The XLH1 is 1440x1080 native not 1920x1080 which means there must be some processing in the camera before the HD-SDI 1080 signal output so I'm wondering if the lag comes from your camera. Also, the actual frame rates on that camera are 59.94, 29.97 and 23.976 for 60i mode, so you should select 29.97 in the drop down menu not 30.
Have you tried to come out of the camera with a Component signal with a 1440x1080 using the DTC-1000 cable to test the lag?
Also, do you have a 1920x1080 camera such as a Sony EX3 you can test your system with.