Saturday night fever seemed to catch on, quite a few people not into the disco scene watched it, so it could have a wider appeal. I've watched most of the little clips that have been put up and the trailer, and I don't know why you've come to the conclusion that they make the film look shit, you obviously have your reasons but to balance your view, I think they make the film look good. To be fair, I can't pinpoint why, I know I got a little tingle watching some of the dance sequences, and it managed to take me way back and I really enjoyed that time of my life, so maybe that's it.
The title is a 'catch all', well too me anyway, lots of people were touched by northern, even if only briefly, and with artists like Duffy and Plan B using dancers, I think there's probably more people will take an interest than we realise. To make something accessible you need a title that's easy to identify with, Northern Soul the Movie pretty much fits the bill in that department, I suppose it could have had a slightly more obscure title, maybe Shrine or The three before eight, for example, but I'm not really sure what that would have achieved, other than to possibly confuse the potential audience. Your last sentence ''It might be great'', is sort of where most of us sit, the majority of posts on Source that I've read are willing it to be good, but we can't make that final judgement until we've seen it, so me, I'm going to do what seems fairly unconventional these days, actually wait until I've seen it before I pass judgement