As far as the topic, JW's 100% have no clue when it comes to people hinting that they get lost, Everybody knows that that is just the truth.
Hey, steady on Free. Yep, you're right that there is a strong tendency among JWs to conveniently ignore hints to get lost, but its far from not universal.
I used to accompany my JW grandfather from house to house and I swear that the householder had to merely utter the words "Not interested" and my grandfather said a polite "Good day then" and departed. He even scolded me on more than one occasion because I persisted beyond householders' hints to go. He was a real gentleman.
Also, as I said earlier, the tendency to ignore hints to get lost seems pretty strong among evangelisers in general. It ain't at all a JW peculiarity. One of my best school friends was from a strict Baptist family and he repeatedly tried to preach the Bible to our disinterested class mates with some painfully embarrassing outcomes (and yes, he was no different from his Baptist parents in that regard).