so far i have read the terms
‘trick’, (Ashley)
‘jamming’, (Ashley)
‘folding’, (moi)
‘snap’, (@SS369)
‘locking’, (@siriuso)
and ‘backflipping’, (@Dan_Lehman)
used to describe this folding action.
here in a post by Xarax, saying
my read is that we are meaning the same thing that i’m (trying) describing as 'segment pulled out and to the (left / right / crossing point / bight) side.
i had considered it a ‘twist’, or a half twist, or ‘swap’, and further a full twist or ‘wrap’, but lacked the knowledge of the names of the parts 
this is the post: Samisen TIB bowline - #2 by xarax
so, 11 years later, I’m commemorating the posts 