Well Known and Active Website User
It is counter intuitive, but if you resite some poetry first or smoke some weed, it will start to make sense. With the thinner gasket, it moves the thicker part of the cap (see 3rd photo above showing the area between the black and red marker) down so when the rocker is at the top of its arc it actually has a little more swing room. Similar (sort of) to having to make sure the rocker isn't a full lift when you unscrew the cap.... so it won't foul that thicker part. Anyway that's my story and I'm sticking to it....for now.....I would have expected a THICKER washer to give more 'head' room inside the cap.