Might be too simplistic but it seems this could come down to volume vs accuracy and judges tend to prefer the former. Add to that Julio was a slow starter so Pryor banks enough early rounds to take the decision.
I go back and forth on this one. A few years ago I'd have definitely picked Pryor but my admiration for Chavez has grown since then. This would be such a tough fight for both of them. The Pryor that beat Arguello was a force of nature so I still lean slightly towards him, but if Chavez can work his magic to Pryor's body... he could slow his workrate and start to claw back the early points deficit and edge it over 15. No stoppage but this one would be full on action from the get go. Great, great matchup.