Truth & Accuracy Of The Historical Record

Deep Throat died yesterday.  Maybe after he saw Frost/Nixon and realized it was another bit of Hollywood playing fast and loose with history.  Elizabeth Drew has a pretty scathing piece in the Huffington Post on the film's distortions.

I have been involved in a fair amount of film adaptations of novels.  The general rule of thumb is to keep the "spirit" of the novel in place.  We feel to change structure, scenes, even characters.  But novels aren't the historical record.
Bio-pics too are a strange breed.  No one's life can be told in 90 minutes.  So again, as a filmmaker, you are chasing your subject's essence.  Often instead of the all encompassing tale, it makes sense to find a particular incident to stand in for the whole.
Yet filmmakers (and marketers) find it so enticing to say "Based on a true story".  Using those words, what obligations do you have?  Films can be propaganda and historical revisionism.  And yet they are always reluctant to broadcast that intent at the head of the movie.  Having seen A BEAUTIFUL MIND and read much about it later, I could not help but be suspicious of FROST/NIXON, so I was waiting for the articles like Drew's to start to hit.
It doesn't matter that Frost/Nixon moves some scenes around (though it's not always clear why), and engages in some invention. But such a gross misrepresentation of such important events -- roughly seventy percent of the population is too young to have been aware of Watergate -- about a figure over whom there is still serious debate, in the name of entertainment and profits, to my mind, crosses the line of dramatic integrity and is dishonorable.
The audience expects the "truth" with weighty historical subjects.  Even more so, they generally accept such films as truth.  Filmmakers need to find ways to contextualize their distortions and help audiences to filter what is being presented.  David Hare's play "Stuff Happens" did this by pulling all dialogue from the historical record -- we recognize that the context of these statements had to have been altered, but that recognition allowed us to look at the substance of the dialogue and characters with a new critical eye.  
With both F/N & W., I felt the filmmakers did not desire this positioning of the record with the audience, and I spent each film wondering what to make of it, whether I could trust it.  Stating that a film is "Based On A True Story" does not help to establish trust between it and the audience; quite the opposite: we have to suspect it all the more.  We need a clear filter when someone wants to serve the truth.  Filmmakers have to ask themselves more why the audience should believe them -- and again we have been shown why they shouldn't instead.