I will probably begin doing this but i will say-- in the past it was not a hurdle at all, and i got many interviews and a few jobs with this name. I have had about 10 interviews in the last year, going to 4th rounds, and nobody suggested it was a problem. my ratio of landing interviews per applications i put in parallels what I am hearing/reading from all other developers on the job market now. I don't strongly suspect my one-letter last name is a huge culprit here, but after a year on the job search and willing to try anything, i may begin applying with a pseudonym
Also, haven't seen anyone mention this yet, but the most famous K is Josef K, of the 'The Trial'. Presumably that's why you chose it. But... you're hoisting a flag of dark cynicism. Reading your blog post, you have seemingly initiated a self-fulfilling prophecy. Getting out of your Kafka-esque nightmare could indeed start with changing your surname, at least informally.
Not any more. The most famous K is from Men In Black now.
I dunno, maybe there's some resume processing program that is used by most companies and an update to it started rejecting your name? Doesn't hurt to try.