Like I said, we've done this a LOT - especially with garlic or onions. Rub it between your hands. Then run one over stainless with cool water
running, and the other over a glass with cool water
running. Then smell each hand... BTW, saying you can smell SOME garlic (like the NPR guy), is not the same ("there was odor
left") - it's not quantitative. Try the left / right thing, and see if YOU notice a difference. It's like saying you spilled gasoline on the deck
, and after wiping it up, you can still smell gas. It's STILL better than before you wiped it up.
And yes, there IS debate about cutting boards. We have only plastic.