I'm like you. A couple of months ago I screened a candidate who listed 'Object-oriented Javascript' in second place on his list of skills. I asked him a really tough, brutal question to test this limits of his knowledge on this:
"How do you do object orientation in JavaScript?"
Blank look. Silence. Okay, let's help him out: "Well, JavaScript doesn't give you a 'class' keyword or an 'inherits' keyword. So how would we write OO code?"
"... To be honest, I've only ever done it in jQuery." he said.
"Oh right, okay. I've never done it in jQuery. How does it work in jQuery?" I asked. Silence again. No hire.
I have no idea why people expect this stuff to pay off. It wasn't a front-end job; OO JS wasn't a job requirement and wasn't listed on the job ad. Why put it so high up on your CV if you don't know anything about it? Why put it on there at all?