"From what I have been told and seen in my collection, the lesser x lesser and or butter x butter have the eye problem about 50% of the time. "

Found this in a similar thread posted a while back
http://ball-pythons.net/forums/showt...-for-400/page3


post #26... this user seems to breed them, or at least have a pretty big collection. Idk how "factual" this is but I tend to subscribe to ppl who offer info based on experience so it may be pretty good info. Like you, I can't find anything that says it decreases the quality of life for the snake. I'll keep looking.