I've seen it. I'm fairly certain it can't be true. The World Trade Center must have been a fairly busy place, and I expect it remained busy 24/7. So people would have seen the charges being set. They might not have known it at the time, but they would have seen someone workmen in odd spaces at odd times, and that's the sort of thing you remember.

Now if 9/11 WAS the work of the Bush administration, why was George W. reading "My Pet Goat" with a bunch of kids?
Why wasn't he at a military base, where he could make a good show as he did when he declared, rather prematurely that the war in Iraq was over?
Or in the oval office at the White House. If the bombers are working for him he's going to be safe. He can make a noble speech about refusing to leave his post when the nation is under attack?
Why, when he finally addressed the American people did George W. make a stupid speech saying nothing in as short a time as possible. Why didn't he have an eloquent address prepared for the American people?
On 9/11, Rudi Giuliani was the man of the hour. If he'd decided to challenge George W. for the Republican nomination in 2008, I think he'd have gotten it. I can't think George W. or Karl Rove or Dick Cheney was happy about that.
So, I'm betting that 9/11 happened pretty much the way they said it did.