Since Michael Moore's films put some heavy digits in some pockets, brah, "documentaries" -- often dealing with political or military topics -- were the hot thing from about 2005 to around 2010.

Does everyone agree with this?

Many, if not, most of them:

1. Present no new information or research

2. Ask no relevant questions

3. Answer no relevant questions

and the worst of them:

4. Do not even support their own claims.

Even the high quality, award winning ones, like Restrepo (2010)(produced by National Geographic) fall into the first three categories. On the other hand, I'm sure the allure of Restrepo comes from that many think it's "cool and entertaining" to see film footage of U.S. Army combat in Afghanistan, filmed as it's happening. But ultimately the work doesn't teach anyone anything at all really.

What do you think about this?

I have no quarrel with a documentary that presents no new information. For one thing, any information is new information, to someone who has not heard it before. For another, asking a documentary to come up with facts unknown to anyone at all in the entire world, outside the production crew, is setting an absurdly high bar - for some subjects, at any rate.

The most recent documentary I've seen is Amy. It was almost all new to me; but I presume that every slightest thing we were told about Amy Winehouse must previously have been known to someone - else how could the filmmakers themselves have found it out?

For another, asking a documentary to come up with facts unknown to anyone at all in the entire world, outside the production crew

Did I say that? I said "present no new information."

Think that through a bit more, son.

Did I say that? I said "present no new information."Yes, but you didn't say what you meant by that, and I was saying that on either of the two most obvious interpretations of your words, you're not making a sensible point.

Information can't be "new" in the abstract; it has to be new to someone. So, new to whom? If you mean "new to some audience" (my first suggested interpretation) then my point is that everything is new to someone. If you mean "new to any audience" then my point is you're setting the bar way too high; the only way a documentary can clear it is by coming up with facts known to nobody in the world ("outside the production crew" was a caveat I charitably added to prevent this condition from being trivially impossible to meet).

And if you meant neither of these things, what did you mean?

Sorry to take so long to get back to you. You are correct. I overshot my position and also poorly phrased my thoughts.

My specific thesis is that the documentary should present information that is "new to any audience," as you put it here:

If you mean "new to any audience" then my point is you're setting the bar way too high; the only way a documentary can clear it is by coming up with facts known to nobody in the world ("outside the production crew" was a caveat I charitably added to prevent this condition from being trivially impossible to meet).

Why do you think the bar is too high?

(To be even more specific, I mean new information unknown to any audience outside the "production crew," and outside the people interviewed on the documentary.)

Presenting no new information depends on what you know about a particular subject. I've learnt a lot of things from docs.

One of the reasons I learn new things is relevant questions being asked, that includes answering them as well. Many docs I have seen do support their claims. Coming from the UK Restrepo highlighted things about American soldiers in Afghanistan that I didn't know before. Otherwise I agree with you.