It's not really a French source, but it is about as bad. This article is referring to the edition of New Yorker magazine coming out next week. Seymour Hersh, who has strong ties to the DemocRats wrote it, and he quotes "former officials", which is probably code for "Clinton people."
Despite all that, I see no reason to doubt the basic premise of the article. Who would not think Rummy would overrule Pentagon generals who wanted a lot bigger force in Iraq? Nothing so far has proven Rummy wrong, assuming he did ordain going forward with a smaller, more mobile force than the old schoolers would have preferred.
Here is what is going on, IMHO. The anti-Bushers know this operation will succeed, but they fully intend to brand it as ill-conceived and mis-managed, no matter the success of the outcome. This bogus noise that we "underestimated" the enemy is the best they have come up with so far.
Saddam Hussein could jump off a building tonight live on Aljazeera TV, and there would be articles written that we thought he was goint to jump last week and our intelligence did not know what floor he would jump from.