I think that most people start to show videos when the game is actually pretty far along in its development. In that you actually have some action in the game to show, not just concept stuff. Personally I think it would be very hard to get any traction behind a game just showing concept stuff. People don't want to have to try and guess what your game will be like, could be amazing, or it could suck there is no way to tell from just a concept.
If you think of the kickstarter videos, people generally have made a basic prototype of the game before they start on kickstarter. And seeing as game development is generally first month is fun creating new things (after which you can have something that looks pretty good), next 4 months is hard slog getting everything to work, building characters and levels etc, it means the kickstarter model can work quite well.
Then there are a few blog journey type ones, where its a diary of building the game, this is a bit different. You probably should have called your video something along these lines, rather than a teaser title. That does give the impression that you actually have some in game stuff to show.