Thanks for your response!
From my personal experiences and research, and I have found this area to be relatively inconsistent. For a larger channel trying to rank for an overall idea, yes you are correct. You want every single tag that relates what so ever. For smaller channels, it is often impossible to rank for things that are only semi-related. With that in mind, I tend to pick one or two search phrases to rank for instead of a whole area of videos. I have found that when doing this adding extraneous tags seems to lower the value of your primary tags. There is definitely a place for using the entire tag box, but oftentimes this seems to hurt results. I'm glad you agree with everything else.