yeah but DDR600 TCCDs running at 3-3-3-8 are sure going to be faster than your leet 2-2-2-5 DDR400
Latency influences stability for the most part, and clock frequency influences bandwidth, therefore in theory, yes lower timings equate to higher memory bandwidth, however you need to loosen said timings and increase your FSB speeds to notice any difference. The real world difference between memory running at 2-2-2 and 3-3-3 at the same frequencies is not noticable.