Not exactly sure where you're going, but usually if I think anything it's more along the line of, "Huh. That reaction seemed contrived." I don't think I'd question, "...if it was captured on video," as I would hope not to notice at all and just roll with it as if it's real life playing out.
I may be misreading you though. Any examples for reference?
EDIT:
This is all within the context of the scene/movie, of course. If the acting is realistic relative to whatever rules the story implies, then I'm good. It's all contextual.
I was actually thinking of a show I like, "Wanted: Dead Or Alive" with Steve McQueen.. He plays a bounty hunter whose prisoner has a bullet in his arm, which needs to be removed. Every time I see it (in this case, just thinking of that scene), I think "Wow, great acting".... He says, "I'll do the best I can". Any actor can memorize lines, but it's the way McQueen said it. He softens the tone of his voice, changing octaves, sounds uncomfortable what he has to do with limited tools being in the middle of nowhere.
After seeing it, I'd always think to myself, "Wow, that's exactly how I'd expect it" - say if there was a hidden camera taking video.. It's ironic because it was a TV sitcom, 22-minutes or so, and they have the tendency to be lean.. McQueen's eyes act better than many who overact or "ham" it up.. It's known that after Steve got a movie script, he'd take a marker and basically cross out the unnecessary dialogue, and didn't seem to have resistance.
Mostly I'm just really happy when someone remembers to say "bye" before hanging up a phone, or remembers to set a time and place to meet, and angry when they lift a phone to their head and you can plainly see it's just the phone's home screen.
There's so many cases similar to what you mention that bug me. They could be corrected so easily, with a minimal amount of observation by the director, etc..
To add, I notice in shows and movies (especially in the older days) how no one ever asks for the price of a drink (or anything else) at a bar or restaurant.. A man just says "Whiskey", drinks it, and throws a coin at the table, and walks out. No change returned, no asking for a bill, no waiter or bartender verifying it's the right amount.