I put one of Bri's hooks on my 97K on a Saturday, then shot the last GP last year with it on the Sunday and beat Brian in the shoot off to win piston class.
Brian took the series though... and then the Worlds... and I went on to have a very mediocre Winter League, but that doesn't make as good a story.
It's all down to how it fits in the shoulder. It's all about forcing a consistent positioning, shot after shot. But yes you don't want it too tight and you don't want to pull it tight to the shoulder.