defaults write com.apple.dock autohide-time-modifier -float 0.4; killall Dock
defaults write com.apple.dock autohide-time-modifier -int 0; killall Dock
defaults delete com.apple.dock autohide-time-modifier; killall Dock
defaults write com.apple.dock autohide-time-modifier -float 0.4; killall Dock
defaults write com.apple.dock autohide-time-modifier -int 0; killall Dock
defaults delete com.apple.dock autohide-time-modifier; killall Dock