The Duckroll (Also called Duckloop by some) is a variation of the Doubleduck technique, it consists on using an alias to make continuous and very fast doubleducks, It is mainly used to control your speed when moving at a very high velocity and to maintain speed when moving towards a staircase, among other useful situations.
A way to bypass that is to use Duckroll as the ducking speed is not capped in the engine. If you exceed that speed, the game will simply slow you down on your next jump. In later versions, including the Steam version, bunnyhopping speed limit is capped to 544ups.
