I'm curious about whether the author tried to optimize Elo's K factor. It's often left at 32, which is not reasonable for all contests. It's essentially related

I'm curious about whether the author tried to optimize Elo's K factor. It's often left at 32, which is not reasonable for all contests. It's essentially related to the standard deviation of player skills: if there is a large range of skills, it should be large, and if there is a small range, it should be small. It's easy to tune by optimisation, and it has a huge effect on predictive ability.