I've seen those claims a lot. I haven't seen references to all the leaks to support it. Do you have any?
(I have seen quite believable motivations for Saddam Hussein to lie, like keeping Iran and the Kurds short. But I have never seen leaks supporting the conspiracy theory that Bush' administration knew the WMDs was a bluff before the 2nd Iraq war.)
I find the naïveté argument hard to swallow. The U.S. has the best intelligence agencies and network in the world.
Interestingly, this exact problem is what is also cited as one of the reasons the Soviets thought the Able Archer exercise in 1983 might be a real NATO pre-emptive strike: senior spies in London and elsewhere weren't told to send their analysis back to Moscow, just their observations. Meaning they defeated the entire point of having spies in place to start with (people who lived and understood the culture being able to explain it to others).