Damn, I can't believe that I didn't think of disabling this dubious feature sooner. Can't even begin to tell you how often an errant fingertip brush makes my Chrome history go backwards (or forwards, for that matter). Turn that shit off with the following command in your terminal.
defaults write com.google.Chrome AppleEnableMouseSwipeNavigateWithScrolls -bool NO
Make sure to restart Chrome for it to take effect.