Wow, this sounds too good to be true.. and well I would be willing to bet it is. There are many things that come to mind:
-How long can you hold that position?
-The search query: top exclusive restaurants manchester, without quotes will seemingly give you a large number of results. (BTW Google shows 157,000. Not 1.5 mil and your video is not on the top) Without quotes Google looks for the words any place on the page. Use quotes shows 1 result, this page!
-Ever heard of “Google Trends”. This tool shows you what searches are popular. Your query returns: “Your terms – top exclusive restaurants manchester – do not have enough search volume to show graphs.” This shows me that it is not worth optimizing for this.
-True SEO practices a balance of the number of times a query is searched and how many times it is used. Sure you can rank quickly for something that no one searches on or that is not being used, but what good is that?? On ths surface that can seem impressive. I would also be very cautious about mass distribution of your site/page/video, the search engines in particular Google consider this spam. It might give a high ranking that is short lived, but you can be penalized or even completely removed from results if you are associated with this.
Bottom line… for page rank longevity, tricks and manipulation search engines can hurt you more than help.