Are the Fallujah "insurgents" escaping?

The NYT reports from Fallujah:

Reports from inside the city said the insurgents were spreading the word that they were not retreating but rather luring the American forces into a "killing zone" deep in the city, though that claim was so far unrealized. …

General Casey said on Monday that his forces had been expecting the insurgents to put up a fight. He predicted that they would probably fall back from an outer ring of defenses and retreat toward the city center, leaving a minefield of improvised explosives to slow the progress of American and Iraqi soldiers.

"What we have generally seen is there's an outer crust of the defense, and then our estimates tell us that they will probably fall back toward the center of the city, where there will be probably a major confrontation," General Casey told journalists at the Pentagon by telephone from his headquarters in Baghdad. …

The invasion actually began 26 hours before the troops charged over the embankment. Beginning Sunday afternoon, Colonel Formica's battalions moved into position, forming an impenetrable chain around the city.

A Falluja resident who tried entering the city on Monday said he had found no way through the seal. The resident said the situation was much different from the situation in April, when Americans battled the Falluja insurgents before withdrawing and when there were many gaps that gun runners could exploit to keep the insurgents supplied.

Yet, those who can't believe the military can get anything right in Iraq have been saying things like:

The main rebel force is long gone. And those that are left are either in hiding, or slipped out of the city under cover of darkness. Remember, Fallujah is the size of Cincinnati. Slipping in and out is a cinch in a city that large, and no blockading force, especially one as small as the one in Fallujah (15-20,000 troops), could completely seal the city. ...

It's all going to hell. ... Most of the insurgents will melt away in the face of the far superior American force. Then the US will be forced either to pull back, ceding the city back to these same insurgents, or we'll garrison the city making our troops car bomb magnets.

Sometimes it seems as though people want bad news so much that they make up their own bad news.