If I did think about it, I probably wouldn't, as I typically take the oven racks out when running the self-cleaning cycle-- there would be no place to put the pan that wouldn't touch the bottom heating element. I figure the (mine, anyway) water pan is always foil-covered during cooks, and it doesn't contact food at any time, so there's not really a compulsion to get it that clean. Brillo pads are more than sufficient for what little needs to be done.