Investigative journalists have more time to find out what happened. The more time they have, the closer they'll get to what happened.
Embedded journalists could only report what they saw at the moment they saw and from the place they were located. Therefore, they had a limited view of the situation.

When the US administration has over and over again claimed that Iraq had WMD's in such amount as to pose a threat to the world, and after all those weeks nothing has been found, but when we've heard about cluster bombs wounding or killing children and the parents being unable to recover their children's bodies because the place was too dangerous to step on, then I wonder.
The "D" stands for destruction (as what cluster bombs are intended for).
Chemical and biological weapons kill, sometimes even slowly, but they leave buildings and goods intact. They don't actually "destroy". Nuclear bombs destroy and kill and that's what everybody had in mind in the first place when the wording WMD was brought up. However, before the war, everybody admitted there were no nuclear threats coming from Iraq.

Raoul