It is a mistake to equate "honesty" with "blurting out the first thing that comes into one's head, no matter how rude, and no matter who is listening".

And it's one thing to take your employee aside for a blunt conversation, and another to broadcast your criticism from a public stage, a stage where the employee's pride is at stake and yet the realities of politics, PR, and media ecology leave the employee effectively unable to respond in kind.

There's nothing dishonest about the phrase "no comment", just as there's nothing dishonest about concealing your body by wearing clothes. It's about privacy. Some things are appropriate for a press conference, some things are appropriate for an all-company email, some things are appropriate for a one-on-one with an employee, some things are appropriate for close friends, and I'm afraid some thoughts are just inappropriate -- there's no shame in having them, but you should show some restraint in sharing them.

And it's true that many people grapple with these principles in the way that one grapples with a strange foreign language, and that engineering culture has evolved to cope with that reality. But Google's not trying to build a social network for engineers. They're trying to build a social network for the world. And if appealing to people beyond the Google culture is business-critical for Google, then politeness is business-critical for Google.