Hi. I Upgraded my MBP (2012), from El Capitan to Sierra and it slowed my computer down to the point where it became unusable. I repaired the permissions, and even reinstalled El Capitan but it didn't help. My MBP is crawling and I'm hoping someone can walk me through a solution. Need help. What can cause this? - Also: I reset SMC and PRAM after update: http://techsviewer.com/macos-sierra-slow-fixes/ - I turned off FileVault encryption due to this site. Thanks!