In case you're wondering how the hell this is actually is getting you a KBD:
Left + Right cancel each other out to Neutral, even if it is Analog Stick Back + D-pad Forward!
So our literal inputs are Back [Down-Back, Back, Neutral, Forward]. When we tap Down, it cancels our Dash into crouch, then when we release the button it returns the stick to "Back." Then when we tap Forward, we get SOCD Neutral (Left + Right), and it returns the input from Neutral to Back as soon as we release, giving us our Back Dash!
Just a little ergonomic input science for ya'!