For one, the bot match tests themselves cannot be used to accurately compare systems. The bot match tests utilize "bots" that are players controlled by AI. CPU power is very important here. Derivations in what the CPU is doing while running the bot match test can actually change the actions of the bots in such a match. So much in fact, that bot match benchmarks run back to back on the same machine can yield a different result. The other problem is the fact that the resultant score is based on the average of both flyby benchmarks.
I don't like UT2K3 because it DOESN'T show real world results. The fps you get in a flyby is worthless, because you don't play a flyby. The botmatch is worthless because its so limited. It will be completely different from what you will see in actual gameplay. Try running the fps counter while playing and you'll see what I mean.
Not to mention that 9700 owners report higher scores in actual gameplay than when they benchmakr. Nvidia owners report lower scores in gameplay compared to the benchmark.
Don't get me wrong. I use UT2k3, 3dmark, Sisoft Sandra,etc. Why, because I can. And nobody has a perfect benchmark, so I use them all. Is it a waste of time? Of course it is. So is using a computer for playing games.