Not sure I see how this avoids an inevitable mining arms race (if it is indeed claiming to avoid such a thing). Even if miners are randomly drafted into random pools, the more miners you create, the more income. Seems like a very game-able system.
The paper linked on github mentions that people are limited to only run a single miner. I haven't parsed it all yet but I think they intend to use the biometrics/HUID to enforce this. Among other concerns, I'm not sure where this leaves folks with injured or missing retinas. Or what might stop people from selling vote or mining capacity by proxy.
When I read about using both iris as unique identifier, it came to my mind this question:
The iris of a living been do not change with age ?