Did Vegeta already know Kienzan before visiting Earth?

[Warmmedown]

He used a quick kienzan on Gohan's tail. Did he learn it from watching the monk use it? Or did he already know how?

 

[Hector]

He already knew.

 

[Warmmedown]

Damn, Vegeta sucks. Can't learn as fast as Goku or Tenshinhan.

So he knew right away that the kienzan should be dodged? But he waited late to tell Nappa, because he assumed Nappa would already know to dodge it? From the anime I got the impression that Vegeta only realised it needed to be dodged when it was already close to Nappa.

 

[SSJ2]

In the manga they don't show Vegeta reacting to it until he was screaming at Nappa, so it's debatable as to whether he was already familiar with the attack or was smart enough to understand it.