Gruber's actual comment: "I don’t know if this signal-degradation-in-left-hand thing is really a widespread problem or not yet, but it’s not reasonable to tell people not to hold the phone this way."
He's mentioned that neither himself or anyone of a number or friends he's asked has been able to reproduce the problem. How could he possibly write exhaustively on the topic at this point, given the lack of information and personal experience of it?
You are assuming that it is a big fuck up that affects a lot of units and/or people, and that the way a phone is held usually doesn't affect its reception. You are also implying that the iPhone 4 antenna has worse performance than its predecessors. Neither of these things are conclusive, and some reports suggest the opposite.
Hypothetically, what if these things aren't true, then what would be the appropriate Apple response?
Kind of disappointed since I expected some kind of ass-pulled argument about what Apple wants.