This sentence: "The Event Rating each player threw prior to the semifinals is calculated." only refers to the Worlds Event Rating which only averages round ratings thru the semifinals since there are no ratings in the 9-hole finals. The Average Event Rating of a player's best seven events (the two Major/NT/ETs are double weighted) that is used to determine the POY finalists doesn't change for the final calculations. That value is currently weighted at 35% in the final calculations and the Worlds Event Rating has a 20% weight.
Rater of the tossed arc.