The way I am reading it, an athlete's performance ranking is the average of all their race rankings in the time period.
This doesn't encourage racing to me. It encourages people to only go out and run when they are in top shape and conditions are good. Hit your minimum events and then don't risk a bad race.
How are DNFs handled? I don't see that. Should a runner quit any time they have a bad race?
Why aren't the rankings capped to your best handful of races in the period?
No. You are incorrect. It's an average of your best performances. Your 3 best performances in a distance help.
We did the math this morning. Paul Chelimo says he wouldn't have made it in 2016 but that's not true. He would have been ranked 25th in the world and easily gotten into the 5000. Here are his top points from 2016.
USA Indoors - 7:39.00 . 2nd place. 1183 points for time + 35 bonus points for 2nd = 1218 points
World Indoors - 8:00.76 in final and 7th place. So 1051 points + 110 bonus = 1161
Pre Classic - 13:21.61 - 13th place SB - 1132 points. (Not included)
US Trials - 1335.92 3rd... 1081 points + 70 bonus points= 1151.
So Chelimo would have had average of 1176.67, Right now that would rank him 25th in the world. Top 42 make it.