That doesn't matter, see other comments below on Google's changing treatment of this attribute.
Also you'll find spambots posting on any open form on the internet even if it doesn't do them any good, because much of it is automated, so even if you hide the results the spam will still come in.
I used to think that spammers would stop if their spamming didn't win them any results. But they don't care. They spread their spam as widely as possible without trying to prune out the places where it does them no good.
Also you'll find spambots posting on any open form on the internet even if it doesn't do them any good, because much of it is automated, so even if you hide the results the spam will still come in.