I have those same grates for my kettle (although not nearly as clean!) and there is a huge difference in temp between the coal side and the indirect side, even if you don't use fire bricks as a divider.
For steaks I sear on the coal side and then move to the cooler side till done. For tri-tip, I use the reverse sear method and cook on the cool side and then finish with a sear. If I was to guess I would say there is at least a 200 degree difference between the two sides.
“If you don’t know who I am, then maybe your best course would be to tread lightly.”
For links to all my BBQ Brethren recipe posts, click http://markandteri.com/recipes.htm