In reference to trying to downgrade a perfectly wonderful, two day old, fully configured, AMD XP 2100 with Win XP to Windows 98 (no drivers or hardware documentation) because a client "didn't like windows XP," I spontaneously responded with...
It might work but it's like trying to make orange juice with a cheese grater
*rim shot
And another client, over the phone...
"You know, you're smarter than a tree full of owls."