Method off progression for advanced moove

Hi every one, 

i'm curious about what method of progression is utilised for learn advanced moove on rings like D skill. I see many gymnast do some static  with a little pause between 8 ( 3 x lsit to straddle planch hold 3 sec ) its seem more efficiency than just assisted hold even for more time under tension ? 
For new skill element have you some method off learning and progression ? is it preferable to cut the element on different phase or working it on global with assistance like ring strenght trainer and how to now when add resistance ? ( exemple nakayama with strap do 10 nakayama on the road for increase the leverage ) ? 

Thx for your knowledge