I can run Doom III with a GeForce2 (Score 1)

I have a 2Ghz, 512MB Ram and a GEFORCE 2 GTS and I can run Doom III! :p FPS is not great but it *is* playable. I don't understand how come the minimum requirement for the game was a GeForce 3... Is my card supposed to support the game? Why then didn't id lower the minimum specs. then?