I've already cleaned the gutters and done the house work. I don't have a wife.
It doesn't count unless someone is standing there, telling you how to do it as well. Double credit if that person has never actually done it themself.
Another way to apply this principle is to have a kid. Then you get to find out how many "perfect" parents there are in the world who can tell you everything you're doing wrong.
You can always tell the "perfect" parents. They're the ones without children.