I'd say in casual day-to-day newsroom talk, when people say "headlines" they really mean "teases". But many producers (yes, myself included once upon a time) will sometimes write teases AS headlines.
The problem is, a good tease goes somewhat against the better angels of our journalistic nature-- to write a good tease, you have to make the conscious decision to leave out information. We as broadcast writers tend to want to put everything we can in a story.
And what's frustrating to me, Jim -- as a television news viewer -- are "teases" that are misleading, deceptive and sometimes outright false. As a journalist, I cringe when I see them because they could cause news consumers to mistrust us even more than they already do.
Hopefully, discussions like this one -- and articles like that written by Ken Keller in December's TuneIn -- can help TV writers and producers improve their tease writing abilities.