Run enough fight cards through a rating model and a pattern emerges that is mildly humbling for anyone who builds them. The betting line is usually closer to the truth than the algorithm is.
Not always. Not by a lot. But consistently enough that it is worth asking what the market has access to that a rating system does not.
Two different questions
An Elo or Glicko implementation answers a specific question. Based on results against common opposition, adjusted for opponent quality and recency, who is the better fighter?
That is a good question. It is also not the question a betting market is answering.

