Adjusting yoyo?

In the slack trapeze video Andre does a trick in which he takes the yo-yo in his hand and it looks like a sidewinder. What’s is the name of this trick and what is it’s purpose?

Thanks ;D

i don’t know the name but its for adjusting sting tension. hes playing unresponsively so he has to tension his string some how.

There’s a great video on string tension under the Learn section.