alanback: The problem is that building this into the formula doesn't have any effect on those that choose not to play at all.
If there was some way to penalize not playing, perhaps some sort of natural decay could be built in to the rating.
Alternatively just remove players who don't either start or finish a game in a set period (I suggest 3 months). If they play again after that they get a provisional rating again.
(gem) Hvis du er interesseret i udviklingen af en turnering du spiller i, kan du diskutere med dine modspillere i denne turnerings forum. (HelenaTanein) (vis alle tips)