I think it's an accurate representation of what happened.
Hamilton and Keane don't say they think it would was designed to fail, they merely mention rumours, whether they believe it or not, we don't get to find out.
However...
(and this is where the pwnage starts)
Conspiraloonies don't quote the next line from Hamilton's book;
Hamilton and Keane believe the commission was a total success!
Here is an interview with Lee Hamilton about his book:
"Without Precedent: The Inside Story of the 9/11 Commission".
http://www.cbc.ca/sunday/911hamilton.html
'Solomon: Do you consider the 9/11 Commission to have been a success, and if so, under what ways do you measure that success? How do you call it a success?
Hamilton: The 9/11 Commission was created by statute. We had two responsibilities -
first, tell the story of 9/11; I think we've done that reasonably well. We worked very hard at it; I don’t know that we’ve told the definitive story of 9/11, but surely anybody in the future who tackles that job will begin with the 9/11 Commission Report. I think we’ve been reasonably successful in telling the story. It became a best seller in this country and people showed a lot of interest in it.
Our second task was to make recommendations; thus far, about half of our recommendations have been enacted into law, the other half have not been enacted. So we've got a ways to go. In a quantitative sense, we’ve had about 50% success there. In a qualitative sense, you could judge it many different ways. But we still have some very important recommendations that we think have not yet been enacted that should be. '
So a total success, or a partial sucess? He says that he thinks that they did a good job, and where 'reasonably successful in telling the story.' Define success. If you define it as he thinks did a good job, success. If you define it as telling the story of 911, 'reasonably successful'.
Regarding the bit about 'being set up to fail', here we have it from the horses mouth:
'Solomon: You write.. the first chapter of the book is 'the Commission was set up to fail.' - my goodness, for the critics - who suggest that it was indeed set up to fail as some kind of obfuscation - you certainly dangled a juicy piece of bait out there in the river.
Why do you think you were set up to fail?'
Hamilton:
Well, for a number of reasons: Tom Kean and I were substitutes - Henry Kissinger and George Mitchell were the first choices; we got started late; we had a very short time frame - indeed, we had to get it extended; we did not have enough money - 3 million dollars to conduct an extensive investigation. We needed more, we got more, but it took us a while to get it.
We had a lot of skeptics out there, who really did not want the Commission formed. Politicians don’t like somebody looking back to see if they made a mistake.
The Commission had to report right, just a few days before the Democratic National Convention met, in other words, right in the middle of a political campaign. We had a lot of people strongly opposed to what we did. We had a lot of trouble getting access to documents and to people. We knew the history of commissions; the history of commissions were they.. nobody paid much attention to 'em.
So there were all kinds of reasons we thought we were set up to fail. We decided that if we were going to have any success, we had to have a unanimous report, otherwise the Commission report would simply be filed.'