How common and accepted is it in documentary circles to lie and mislead interviewees by telling them you have one goal while secretly pursuing another? I ask because it seems to be an accusation leveled at documentary filmmakers when they have managed to include a "hostile witness" or anyone who disagrees with the film's central idea. So do people making documentaries go in with that goal - to lie in order to get the interviews - or is the making of a documentary such fluid and uncertain work that you can barely pin it down before it is finished? That's the best benefit of the doubt I can assert here, and it sounds weak.
Mokalus of Borg
PS - It's also possible that interviewees misunderstand the situation.
PPS - But just as possible that this was the intended result.