Again Not, just a block...
The main theme of Karate is not what it seems.
Anytime Instructors of olden time would give you a Kata, Karate Action or Bunkai application, they would merely call it a block. However that was just an easy and obscure label.
Most were not inquisitive or bold enough to question the validity of these applications in real situations. Gedan Barai is no different, labeled a "Down Block", was easier than describing the lethailty or real affects on another human being or opponent. They did it mainly to hide the real Karate application as well as keep it from being researched and more uncovered throughout the style.
Let's find out what else this will do to an opponent, the power, the potential and the affects...