>> 'Questions that have "tricks" in them basically never fall into the latter category.'
They also leave a bad impression for the candidates: You feel bad for not getting the answer, or you feel the interviewer was trying to trick you, or that he's trying to show off.
I'm firmly with the original post - I have been jerked around by the Google interview process twice now, and I'm just not interested any more. Your process sucks.
Not as the person who prompted you to ask this, but let me (rudely) interject and give my own answer, if you'll forgive me;
1. CLARITY is very important. Your workflow and process aside, it's the person on the phone who we interact with and get any barometer into, and this is something I've found very painful in my own experiences with Google interviews, either...
A. They ask a question, or respond to a question in a way that is very difficult to not get thrown by. In my own experience, this was being asked to implement an RB tree on the fly (when I've told my friends inside the big G that I was asked this they always go "wait what", but my hand to god, this happened.), and when I responded with "I'm sorry, that datastructure relies very heavily on getting some very precise rotations right that I simply don't have memorized. Can I look them up and try going from there?" I was met with "Hm, no, let's move on, I would normally just expect my interviewee to just know the answer", a response which, to put it VERY lightly, added insult to injury. Or...
B: Accent. I realize this is probably a sensitive subject, and I don't mean this in a "everyone should speak English flawlessly", but if you're communicating over a more lossy medium like phone, you have to be aware that a heavy accent only contributes to the difficulty in shared understanding, which contributes to feeling stressed and confused, which... etc, back and forth. Multiple Google interviews I was a part of occurred with interviewers I could barely understand, and regularly had to ask to repeat themselves, which I'm sure on some level to the interviewer didn't help impress me to them.
2. Feedback and culture. Despite the above, I had the opportunity to intern at Google. I was always somewhat proud (I promise I'm not trying to dick-wave in this, bear with me :) ) that my feedback from my manager reported me as at or above expectations, however, I was told in no uncertain terms that I was not a good culture fit (Admittedly, I was 'young', and needed a good smack on the head, but it really bites that perception is valued more than contribution, especially when you're not given actionable ways to improve), and never received a single atom of feedback, either in my tenure there or during the interviews ("you could have perhaps solved that like X", sort of things) to put me at ease or give me any sense that there was room for personal improvement. I realize the potential legal ramifications in this, but, it's a problem, it needs to be improved, I refuse to accept that with all the smart people at G a solution can't be found :)
Sorry for the rant, this has been a subject that's been itching at me for a few years now, and the chance to braindump at someone who might actually have visibility into the why/how of all of this is very welcome.
They also leave a bad impression for the candidates: You feel bad for not getting the answer, or you feel the interviewer was trying to trick you, or that he's trying to show off.
I'm firmly with the original post - I have been jerked around by the Google interview process twice now, and I'm just not interested any more. Your process sucks.