The ironic thing about this trope is, the better the actor, the less it should work. Unless they've been told to react to whatever happens, the natural response is presumably to avoid deviating from the script.

What about Stage Moms making faces at the actors beside the camera, does it count?

In "The Silence of the Lambs", when Clarice is talking to Lecter and he starts mocking her Virginia accent, Hopkins had not told Foster he was going to do that, and her offended expression is genuine.

The examples in this article are kind of a mess with a whole lot of examples that don't even follow the trope and some that are mostly about method acting instead of being forced method acting. Also, many examples aren't really explained so that one could understand the point behind them.

"As early as the first Terminator crew members wore T-Shirts emblazoned with "You can't scare me. I work for James Cameron.""