Just a little note for myself in case I want to play around with this later.

From Cult of Mac:

Here’s the text to paste into Terminal:

To speed up:

defaults write com.apple.dock expose-animation-duration -float 0.15

For super fast:

defaults write com.apple.dock expose-animation-duration -float 0.1

For slow:

defaults write com.apple.dock expose-animation-duration -float 1

To disable animations:

defaults write com.apple.dock expose-animation-duration -float 0

To return to normal:

defaults delete com.apple.dock expose-animation-duration