I just wanted to briefy mention that I have had a few phone interviews over the past few months that I've felt better about, even though I didn't make it to the next round in any of them. I have changed my interviewing strategy somewhat. I am maintaining my focus on IETF working group activities and some other things (such as ranking methods). So when I do have an interview coming up, I don't just drop everything else to prepare for the interview, although I do attend to specifics the interview might require, such as writing code in a Google Docs document. When writing code during an interview, I make sure to ask questions, such as if pseudocode is allowed, if I may refer to documentation (e.g. man pages), etc. If a particular language is required, I check myself as I write for matching braces, etc. Also, after asking questions, I ask to gather my thoughts for a minute. If I cannot think of a more efficient algorithm or method, I write the more straightforward code I can think of that would (hopefully) suffice.
In general, I have felt more in control of these interviews than others I've had (and written about here) in the past. Hopefully, that is a sign of better things to come.