I'm not sure if this letter is more cruel, pathetic, or humorous. If there was the slightest chance that more than a dozen or so Egyptians were paying the least attention to these folks, the letter would be extremely cruel. What the Egyptian people need right now, and the very best we have any rational cause to expect will happen, is for them to get a moderately decent government that can establish something vaguely like the rule of law and not loot them too much. If any Egyptians were actually listening, to advise them to reject such a government and hold out for the fantasy land of these theorists would be a vicious act indeed.
It's also kind of pathetic in the level of self-centeredness the letter displays. The Egyptians are going through a traumatic upheaval right now, but that's not what is important: what is important is the comic book fantasies of these twenty people sitting back comfortably on their couches in the United States.
And the letter is humorous if you try to imagine what the signatories are thinking: Do they really see the crowds in Tahrir Square circulating this letter, slapping themselves on the head, and saying, "Allah be praised: we do not need a government after all!"