Wow, who pissed in your Corn Flakes this morning Brian?Sure they are. Haven't you seen those heart tugging, "you grow Liberty because you have a family that supports and loves you and depends on the exceedingly great profits of liberty canola to provide for them by growing brand x" commercials? ;-)
With material like that, how can you go wrong. Invoke an emotion. Marketing 101.
Yield data is showing the better ones are all pretty much the same when averages and promotional material is generated. You may notice that the Y axis on the yield difference spread is maybe 2 to 4 bushels - yet more clever marketing to make you think it yields twice as much as a competitor. Also how there is 3 or 4 varieties featured yet they all have different checks so you cant compare anything and you have no idea how they actually performed. Or how certain companies simply drop trials they don't win at. Shame on you, you know who you are!
That said, certain varieties perform better in certain areas. That is where you doing your own real research pays off for your own farm, in your own local area. You would never think it could be so specific, but it is fascinating to observe. And is the main reason why there isn't a 'best' overall canola - no clear winner - in a wide geographical area such as provincially, western canada or especially combine forum.
You need to find your own winner, with your farming method, rotation, fertility, land, rainfall..... But alas, that takes work and most simply don't bother. They pick the best rep who buys them the best trips.
Does anyone have trouble picking a flax variety? Nope. Seed companies don't give a crap which variety i grow - they don't make obscene profits from it like canola.