Here are my thoughts while researching this method (Maybe the OP can clear a few things up), as so far I'm not seeing great potential for ranking videos instantly (within a few days) or effortlessly (just posting the video with no promotion: views, likes, etc.):
1 - First of all, finding KW's with lots of EXACT searches and no youtube videos is rare.
2 - For some of the keywords I've found there are no yt videos on the first page of google, but when you search for that KW in yt you'll see LOTS of videos. As an example, let's say that your KW is "pretty blue pigeons", if you searched youtube you'll see lots of videos like:
Look at the pretty blue pigeons we just saw
The funniest pretty blue pigeons videos
Some pretty blue pigeons epic fails
etc, you get the idea
So my guess is that simply being the first one to post a video with the exact title "pretty blue pigeons" isn't going to get you anywhere.
3 - I've seen quite a few KWs where someone posted a video with the exact title "pretty blue pigeons" and is no where on the first page of google, however there is a video "some pigeons that I filmed were blue" ranking on the first page of google. AND the guy who posted the video with the exact title did so 2 years ago, but the guy who's ranking WITHOUT the exact title only posted his video one year ago.
4 - Checked a lot of KWs were they seemed like they might work, until you search it on yt and see that there are 500,000 videos returned.
I'm not slamming the OP, but it seems more detailed info (on competition in yt, etc.) is needed. Maybe the OP can let us know what his / her personal experience has been in these situations, and more details are ALWAYS better.