[1] Yes yes, I'm aware that this example isn't perfect because it could mean different things depending on the language
Interviewees, however, tend to get flustered if they can't remember the method names. It's another rock on a pile that eventually leads to nervousness collapse, something that happens far too often, so after a few dozen interviews I've started stressing up-front that no, it doesn't matter, I'm not scoring you on that.
That, on its own, produced a measurable increase in average score.
That's pretty vague. I use the same strategy as the sibling post, ratcheting up difficulty until the candidate fails, so I usually have a lot to go on, but the exact criteria end up changing from one interview to the next depending on what the candidate did.
Occasionally I end up with not enough data. I try to give my feedback in the form of a confidence interval, but if it's mediocre candidate combined with not-stellar signal quality... figuring out how to score them can take a while.
When I interviewed at Google, a major part of the rejection feedback they gave me was "we felt like you weren't worried about whether your code would really run".