The videos may be relevant, that does not mean that the people who uploaded the video used the correct and relevant tags from Google's Keyword Tool.
Telling people to grab tags randomly will not help anyone.
If you've used Google's Keyword tool then you know just how often it returns keywords that are in fact not relevant. This is because it is guessing based on statistical data from user searching. It takes vetting to utilize the Google keyword tool just as it would to use other videos as keyword research. One cannot just put a few words into the keyword tool and use everything it spits out because much of what it "suggests" won't be relevant to the video in question. If you could then that would be a far superior method in both accuracy and in time. Insert base keyword, sort suggestions by competition and/or search volume, use all. Thing is, nobody does this because half the list is garbage for your particular video.
I also didn't suggest people do random poaching.
What I did suggest was to type in the most relevant search you can think of based on the content of your own video. YouTube by default sorts by relevance which gives you a source of very relevant videos and by extending the logic that Google knows what it's doing, also have relevant tags. It is entirely likely that they will also have tags that aren't relevant like the posters name for example, thus the portion of my suggestion to remove those.
