Cluster modes - a deeper description avaialble?

Thanks. I was not after the current implementation, more after like a small description about the principles of each clustering mode. The more that I have reported a bug with them: Phantom detections in cluster modes != 0

Especially I’m curious about, why the cluster-mode 0 is unable to deliver confidence values. Why isn’t it possible to average the confidences of each of the clustered detections? Or even median it?