In the handyman column in this Sunday's paper, a reader solicited advice on getting stubborn stains out of a tub and the answer surprised me. The columnist advised the reader to wet the tub with hydrogen peroxide, sprinkle on cream of tartar, wait hours to overnight then scrub. It wasn't entirely clear if the reader had rust stains or other deposits. I haven't tried this yet and wonder how it's supposed to work. Does anyone understand the chemistry of this process? Or is it just bunk?